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MCAT – BIO: Print and Highlight in PDF most bio molecules:-lipids-proteins-carbohydrates-nucleotide derivatives70 to 80 % water is cellwater, small polar molecule, can H-bond
allows it to maintain liquid at roomcohesive forces squeezehydrophobic away from H20hydrophilic dissolve easily
-negative charged endsattract the posi H’s ofH20.
Most macromolecules can be hydrolyzed, andformed via dehydration.lipid – low sol in H20, high sol in nonpolarmake good barriers1) Fatty acids2) triaglycerols3 phsopho lipids4) glycolipids5)steroids6) terpenesFatty acids are building blocks for most lipidsSaturated FA’s
Æ^ only single C-bonds Unsaturated
Æ^ one or more double C-C bonds most fats reach cell as FA, not triaglycerolstria’s are 3 carbon backbone – stores energy--also thermal insulation, etc.glycolipids have 3-C backbone with sugarattached. membranes of myelenated cells innervous systemsteroids – 4 rings. include hormones, vit D,and cholesterol (membrane)Eicosanoids – local hormones – bp, body T,smooth muscle. Aspirin commonly useinhibitor of prostaglandins.lipids insol, so transported in Hb vialipoproteins. classified by density, VLDL,LDL, HDL. (lipid::protein ratio).---- Proteins: chain of aa’s linked by peptide bondsaka polypeptides
in humans, 20 alpha amino acids
amine attached to alpha carbonyl 10 are essential.aa’s differ in their R group.digested proteins reach our cells as single aa’s Nonpolar: Gly ,^ Ala
, Val, Leu, Iso, Phe, Tryp, Met, Pro Polar Ser, Thr, Cys, Tyr,
Asp ,^ Glu
Acidic Aspr Acid
,^ Glu^ acid Basic: Lysine,
Arginine
, Hist (italics for mnemonic)Proline induces turns.2 types of proteins – globular and structural.glob: enzymes, hormones, memb pumpsstruct: cell / matrix structure. collagen. glycolproteins
- cell matrix cytochromes
- prothetic heme group. Hb ---CarbohydratesC and H20. C(H20). Glucose – 6 C’s. allsugars broken down to glucose.-2 anomers, alpha (trans) and beta (cis)Animals eat Alpha. Bacteria break Betaabsence of insulin, neural and hepatic cells usefacilitated txport for glucose.cellulose has beta linkagesif you see N on the mcat, think protein---- Nucleotides: 3 components-5-C / pentose sugar-Nitrogenous base-phosphate groupbases in nucleotides – AGCT and Upolymers: DNA, RNA, Nucl-acids
joined by phosphodiester
nucleotides written 5’ to 3’DNA written so top strand is 5’
Æ3’
bottom is
Æ5’
RNA is 1-stranded. U replaces T.important nucleotide: ATP. energy. cyclicamp
is a messenger.
--- Enzymes globular proteinscatalysts
lower activation Enot consumed, altereddo not alter Keqlock-and-key theory / enzyme specificity.specific shape.second theory: induced fit. Shape of bothenzyme and substrate altered during binding.enzymes
Æ^ saturation kinetics. as [substrate] goes up, so does rxn rate, butcurve slows as gets closer to Vmax.Km good indicator of affinity for its substratetemp and pH.in human body, temp of 37Cpepsin in stomach likes ph< 2. Trypson, insmall intestine likes ph between 6 and 7.most enzymes require non-protein componentcalled cofactor.
Æ^ optimal activity. Cofactors:Minerals,Coenzymes (many are vit’s of theirderivatives)-cosubstrates-prosthetic groups. Æ^ bind to specific enzyme, txfer chemicalgroup to another substrate. cosubstrate thenreverted back.ATP is cosubstrate type of coenzyme--- Enzyme inhib
-irreversible
Æ^ covalently bonded (penicillin) -competitive
Æ^ raise apparent Km but notVmax -noncompetitive
Æ^ some other spot, changeconformation. lower Vmaxdo not change Km Regulation:-zymogen/proenzyme – not yet activated.need another enzyme or change of pH. eg,pepsinogen.-phosphorylation-control proteins, eg, G proteins-Allosteric interactions: negative or positivefeedback mechanism. negative
: product downstream comes back to inhibitpositive: product activates first enzyme.occurs much less often.other proteins have these characteristicsnegative allosteric inhibitors do not resemblesubstrates, they cause conformational change.can alter Km without affecting Vmax.
positive cooperativity. low [substrate], smallincreasees in [substrate] increase enzymeefficiency and rxn rate. positive are the firstchanges. it’s why there is an 02 dissociationcurve with Hb. (sigmoidal shape). bothpositive and negative cooperativity. Enzyme Classification: memorize “-ase” sometimes complexchemical has “ase” and you will know it is anenzyme, it contains nitrogen, and it is subjectto denaturation.lyase – catalyzes addition of one substrate to adouble bond of a second substrate.ligase also governs an addition rxn, butrequires energy from ATP.kinase – enzyme which phosphorylatessomething, phosphatase DEphosphorylates.eg, hexokinase phosphorylates glucose as soonas it enters cell to prepare for glycolysis. Metabolism
: all the cellular chemical rxns 3 stages1) macromolecules broken down intoconstituent parts (little E released)2) constituent parts oxidized to acetyl CoA,pyruvate, or other metabolites forming ATPand reduced coenzymes (NADH and FADH2)which does not directly utilize oxygen3) if O2 is avail, metabolites go into TCA andoxidative phosphorylation to form largeamounts of energy (more NADH, FADH2, orATP); otherwise, coenzyme NAD+ and otherbyproducts either recycled or expelled aswaste. 2
nd^ and 3
rd^ stages, the energy acquiring stages, called respiration. aerobic andanaerobic versions.anaerobic: 02 not required.glycolysis first step. glucose
Æ^ pyruvate (3C’s).+ 2ATP, PO3, H20, 2NADH happens in cytosol (fluid portion) of cellsglucose facilitated diffusion into cell.resulting 3-C molecules each transfer one oftheir PO3 groups to an ADP to form one ATPeach in substrate level phosphorylation.Fermentation: anaerobic respiration.glycolysis
Æ^ reduction of pyr to ethanol or lactic acid. humans do the latter. no 02 availor unable to assimilate E from NADH.fermentation recycles NADH back to NAD+
Aerobic Respiration – requires O2. productsof glycolysis will move into mitochondrialmatrix. inner mitochondrial memberate lesspermeable. Once inside matrix, pyr convertedto acetyl CoA producing NADH and CO2-- Krebs CycleAcetyl CoA – coenzyme which transfers 2carbons to the 4 carbon oxaloacetic acid tobegin krebs cycle (aka TCA).
Each turn
produces 1ATP, 3NADH, and 1 FADH2.ATP production is substrate-levelphosphorylation.
during cycle, 2 CO2 given off. oxaloacetic acid is reproduced, cycleagain. Proteins
Æ^ aa’s
Æ^ Pyruvic Acid + NH (waste)
Æ^ Acetyl CoA
Æ^ TCA/Kreb’s
Fatty acids
Æ^ Acyl CoA + NAD+ +
FAD^ Æ^ Acetyl CoA
Æ^ enter TCA/Kreb’s
Polysaccharides
Æ^ simple sugars
Æ^ PGAL
Æ
Pyr acid
Æ^ Acetyl CoA
Æ^ TCA/Kreb’s
aa’s are deaminated in the liver. chemicallyconverted to pyr acid or acetyl CoA. Electron Transport Chain (ETC) series of proteins, including cytochromes withheme, in the inner mitochondrial membrane.electrons passed down series and accepted byoxygen to form water. protons are pumpedinto intermembrane space for each NADH.
Æ
proton gradient
Æ^ proton motive force
Æ
propels protons through ATP synthase to makeATP. Oxidative phosphorylation. 2-3 atpsmanufactured for each NADH. FADH2similar fashion. only 2 ATPs, however.intermembrane pH lower than matrix.Glucose + 02
Æ^ CO2 + H20 (combustion rxn)final electron acceptor is 02, that’s why it’saerobicAerobic Respiration: 36 net ATP, includingglycolysis. 1 NADH brings 2-3 ATPs, and 1FADH2 brings about 2 ATPs. One glucoseproduces 2 turns.
Genesgene – series of n-tides. codes for singlepolypeptide, or mRNA, rRNA, or tRNA.Eukary’s have more than 1 copy of somegenes. Prokary’s only have 1 copy of each.one gene; one polypeptide. exception: posttranscriptional processing RNA.Genome: entire DNA sequence of organism.only ~ 1% of genome codes for proteinhuman DNA differs only at about 0.08%.Small variation
Æ^ big difference. Central Dogma: DNA transcribed to RNA,translated to aa’s for proteinDNA
Æ^ RNA
Æ^ Protein. (same for all organisms) 4 bases of DNA: -Adenine (purine) – two ring-Guanine (purine) – two ring-Cytosine (pyrimidine) – one ring-Thymine (pyrimidine) – one ringeach n-tide bound to next by phosphodiesterbond b/w 3
rd^ carbon of one deoxyribose and the phosphate backbone of a single strand ofDNA with 5’
Æ^ 3’ directionality. In DNA, two strands run antiparallel boundtogether by H-bond. Double stranded. h-bonding
Æ^ base pairing. complementary strands
Æ^ double helix
each groove spirals once around double helixfor every 10 base pairs.diameter of double helix is 2 nanometersremember: Ntide made of pentose sugar, P03group, nitrogenous base.pairings: AT, GC2 H bonds in A-T, 3H bonds in C-G“A2T, C3G”DNA replication: semi-conservativenew dbl strand created
Æ^ has one new one
old. Replication proceeds in both direction fromorigin – each direction produces a leading andlagging strand.Prokaryotic replisomeDNA polymerase builds the new strand.Requires RNA primer to get started.
reads parental in 3
Æ5 direction
complementary strang 5
Æ^3
convention: DNA nucleotides 5to
as well
5 Æ3. 5 is upstream, 3 downstream.“reading DNA like paddling upstream”5 steps of replication:1) helicase unzips double helix2) RNA polymerase builds a primer3) DNA polymerase assembles leading and
lagging strands
- Primers are removed5) Okazaki fragments joinedprocess of replication: semidiscontinuoustelomeres: ends of eukaryotic chromosomalDNA. protect from chromosomal erosion RNA carbon 2 not deoxygenatedsingle strandeduracil instead of thyaminecan move through the nuclear pores3 types-mRNA: delivers DNA code for aa’s tocytosol for protein manufacturing-tRNA: collects aa’s in cytosol, transfers toribosomes-rRNA: combines w/ proteins to formribosomes
Æ^ protein synthesis. DNA is produced by replication
only in nuc and mito matrix RNA by transcription
also in cytosol transcription: starts w/ initiation. promoter.RNA polymerase. promoter is upstream fromgene.replication: transcription bubble, elongationmode. strand transcribed: template orantisense. other strand is coding. RNA poly,like DNA poly, reads in the 3
Æ5 direction,
building new RNA to be made 5
Æ^3
no proofreading mechanism. slower. rate oferror is higher. not hereditary errors. end iscalled termination.
Coding strand resembles
RNA transcript.replication doesn’t distinguish genes.transcription decides this. most regulation ofgene expression during transcription byactivators and repressors. bind to DNApromoter, and either activate or repress RNApoly. can be allos regulated by smallmolecules such as cAMP. respond to envirochanges.eukaryotes: one gene per transcriptprokary: polycistronic
operator + promoter + genes = operoneg, lac operon. codes for enzymes to allow Ecoli to import and metabolize lactose whenlow glucose. low glucose, high cAMP,activates CAP, activates promoter. operatordownstream, too. Allows for repression viabinding to a protein, allolactose (inducer).initial mRNA sequence called primarytranscript. processed by addition of n-tides,deletion of n-tides, modification of n-bases. 5’end capped with GTP. 3’ end poly A tail toprotect from exonucleasesprimary txscript cleaved into introns, exonssnRNPs (snurps) recognize, form spliceosome,cut off introns. only 30,000 genes, but120,000 proteins possible bc of splicing.introns::exons = 24::1denatured DNA – heat
Æ^ separated strands.
more C3G pairs, higher TmDNA-RNA hybridizationrestriction enzymes cut DNA at certainsequences, usually palindromic. leave DNAwith sticky end so they can reconnect.recombinant DNA.DNA library – use a vector in a bacterium,then reproduce bacterium. active gene, turnblue with x-gal. some bacteria wont take up,so introduce lac-z with your inserted vector.introduce X-gal and the right ones will turnblueone way to find gene in library – hybridizationradioactive labeled comp sequence of desiredDNA fragment (probe). cDNA product –mRNA produced by the DNA. lacks introns(good).better cloning: polymerase chain rxn (PCR).fast way to clone dna. heating and annealing.primers hybridize. polymerase replicates.southern blotting: ID target fragments ofknown DNA in large pop of DNA. DNAcleaved into restriction fragments. separatedby size in gel elctrophoresis. large movesslower than small. gel denatures DNAfragments. probe hybridizes w/ and markstarget fragment.Northern blot uses same techniques to IDspecific sequences of RNAWestern blot: detects a protein with antibodiesRFLP: ID’s individuals instead of specificgenes. we are polymorphic for our restrictionsites. can only negate people, cannot identify
Genetic code: mRNA nucleotides.code is degenerative. more than one set of 3nucleotides can code for a single amino acid.but 1 and only 1 aa, so unambiguous.start codon is AUGstop codons UAA, UAG, and UGA.64 possible combinations of the bases20 possible amino acids.if protein contains 100 aa’s, then 20<100possible sequences.RNA n-tides written 5’
Æ3’
Translation: mRNA directed protein synthesis.mRNA the template. tRNA carries n-tidescomplementary for codon, called anticodon.rRNA with protein make up ribosome, whichis the site of translation.small subunit, large subunit. ribosomesrequire nucleolus for their origin.tRNA posessing 5’-CAU-3’ anticodonsequesters methionin and enters at P site.Large subunit joins (initiation). next tRNAenters A site. translocation. tRNA shifts,moves to E site.initiation, elongation, and termination.txlation begins on free floating ribosome.signal peptide can transport polypeptide tolumen. SRP can carry entire ribosome towardsER Mutationsany alteration that is not recombinationgene mutation – sequence of n-tides in a singlegenechromosomal mutation – structure is changedsomatic vs. germ cell mutationslatter more serious point mutation
- single n-tide changed base pair mutation
missense
- bp mutation in aa sequence of gene
may or may not be seriouseg, sickle cell anemia insertion or deletion
Æ^ frameshift
mutation
multiples other than 3.sometimes nonframeshift and still functionalusually frameshift is non-functional nonsense
- stop codon created by mutation chromosomal mutations—deletions—portion of chromosome breaks offduplication – breaks off and incorporates intohmologous chromosomeDown syndrome result of aneuploidy where 3copies of chromosome 21
translocation – segment of DNA from 1chromo inserted into anotherinversion – orientation reversedtransposons can excise themselves and insertthemselves elsewhereforward mutation – changing organism awayfrom original statebackward – back to original stateoriginal state called wild typeCancerproto-oncogenes – stimulate normal growth incells. can be converted to oncogenese – genesthat cause cancer, by UV radiation, chemicals,or simple random mutations. Mutagens thatcause these called carcinogensDNA is 5 ft for each cell. wrapped tightlyaround globular proteins, histones. 8 histoneswrapped in DNA – nucleosome. wraps intocoils, supercoils, entire complex calledchromatin.somatic cell: 46 double stranded DNAmolecules. chromosome. 46 chromosomesbefore replication, 46 after replication.duplicates referred to as sister chromatids.Diploid means cell as 23 homologous pairs.sex cells haploid.stages of cell’s life1) G1 – first growth2) S – Synthesis3) G2 – second growth phase4) M – mitosis / meiosis5) C – cytokinesis1-3 called interphase.in G1 – regions of heterochromatin have beenunwound into euchromatin, RNA synth andprotein synth very active. G1 checkpoint
Æ^ S
stage, if ratio of cytoplasm to DNA is highenough.Gzero is nongrowing state. neurons, livercells.G2 checkpoint – Mitosis promoting factor(MPF)Mitosis, nuclear division w/o genetic change4 stages –remember PMAT:
prophase
(condensation of chromatin into chromosomes,centrioles move to opposite sides of cell.spindle apparatus forms of aster, centromeresat center. spindle micotubules connect twocentrioles.)
metaphase
(chromosomes align
along equator),
anaphase
(sister chromatids
split at attaching centromeres, move towardsopposite ends of cell. cytokenesis, separation
sexual repro occurs between hyphae from tomycelia of diff mating types + and –conjugation bridge.asexual repro: when conditions are goodsexual: when it’s tough. parent less adaptableDefining feature of eukary’s – nucleus. DNAcannot leave the nucleus, so transcription musttake place in nucleus. RNA leaves nucleusthru nuclear pores.nucleus wrapped in double phospholipidbilayer – nuclear envelope. large holes, pores.w/in nucleus is nucleolus where rRNA istranscribed and subunits are assembled.cells can acquire stuff via endocytosis. difftypes- phagocytosis
: memb protrudes outward. started by receptor binding.- pinocytosis
- extracelular fluid engulfed. nonselective- receptor mediated . uptake of hormones and
nutriants. exocytosis
is the reverse of endo. ER^ separates cytosol from ER lumen /cisternal space. ER can be contiguous w/ cellmembrane.near nucleus, ER’s cytosome side has agranular appearance (ribosomes). aka, roughER. Translation on RER propels proteins into ERlumen as they are created. They are taggedand sometimes glycosylated. Newlysynthesized proteins moved through lumentowards golgi. Golgi organizes andconcentrates proteins as shuttled by transportvesicles. end product: vesicle full of proteins.either can be expelled from the cell assecretory vesicles, released from golgi tomature into lysosomes, or transported tooother parts of cell such as mitochond. Secretory vesicles:
may contain enzymes,
growth factors, or extracellular matrixcomponents. release contents thru exocytosis. Lysosomes
contain acid hydrolases (function best in acidic environs). capable of breakingdown any time of macromolecule w/in cell.interior pH of 5. fuse w/ endocytotic vesiclesand digest contents. Problem: can release theircontents into the own cell causing autolysis.happens during formation of tissue, however,to form fingers, etc.
SER^
lacks ribosomes. resembles tubes, not flattened sacs like RER.-contains G6P, which can hydrolyze toglucose, glycolysis.-triglycerides produced in SER and stored-adipocytes-cholestorol formation, conversion to steroidsphospholipids in cell memb formed from SER.oxidizes foreign substances, drugs, toxins, etc.Key in liver. Peroxisomes
- vesicles in cytosol. grow by incorporating lipids. self replicate.overview:1) 2 basic “sides” of cell – cytosol and ERlumen. in order to get to cytosol, substancemust cross membrane via passive or facilitateddiffusion, or active transport. can reach erlumen via endocytosis w/o ever transportingacross a membrane.2) RER has Ribosomes attached to cytoticside. synthesizes virtually all proteins not usedin cytosol. proteins synth on RER pushed intoER lumen and sent to Golgi3) Golgi modifies and packages proteins foruse in other parts of cell and outside4) lysosomes come frome golgi, havehydrolytic enzymes to digest endocytosedsubstances5) SER is site of lipid synthesis, eg steroids.SER also detox’s, eg drugs. Cellular filaments: cytoskeleton determines skeleton and motilityof a cell2 major types of filaments:- microtubules
: larger than filaments. involved in flagella and cillia construction, and spindleapparatus. in humans, cilia only found infallopian tubes and resp tract. rigid hollowtubes made of protein tubulin. spiralappearance from alpha and beta parts. mitoticspindle is made of microtubules- microfilaments
: smaller. squeeze membrane together in phagocytosis and cytokinesis. alsoforce in the microvilli and muscle.flagella and cilia specialized structures frommicrotubules. axoneme contains nine pairs oftubules arrangment 9+2. cross bridges fromprotein called dynein.Eukaryotic flagella made from 9+2microtubule configuration; prokaryotic is justthin strand of protein called flagellin. eukflagella do whip-like action, whereas prok justrotate.
microfilaments smaller than microtubules.actin is major component of microfilaments.contractile force in muscle, also cytoplasmicstreaming, etc.Cellular junctions3 types of junctions that connect animal cells- tight
water tight seal, blocks water, ions, etc.bladder, intestines, kidney. also blocksapical and basolateral movement of proteins inmembrane. fluid barrier around cells- desmosomes –
spot welds holding cells together. attach directly at cytoskeleton. foundin places of stress: skin, intestinal epithelium.- gap –
tunnels b/w cells, allow exchange of small molecules. important in cardiac muscleto allow spread of AP’s from cell to cell.Mitochondriamitochondria – powerhouses of euk cell. krebcycle happens here.endosymbiont theory: mito may have evolvedfrom symbiotic rel’ship b/w ancient prok’s andeuk’s. mito like prok’s: have own DNA thatreplicates independently.
Always inherited by
momma.Sturcutre:-outer membraneinter membrane space-inner membrane (holds ETC chain)(2 phospholipid bilayers, the space in between)-cristae (invagination of inner membrane)-matrixExtracellular Matrixtissue – group of cells of similar function-some tissue have fibroblasts that secretefibrous proteins elastin and collagen---form molecular network that holds tissue in
place (extracellular matrix)can be liquid (blood) or solid (bone) basal lamina
- thin sheet of matrix material. separates epithelial from support tissue. alsofound around nerves, muscle, and fat. acts assemipermeable barrier.Organizationcells of same tissue tend to have sameembryology.4 types of tissue in animals:1)^ epithelial - separates free body surfaces from surroundings.
-simple: 1 layer, eg heart-stratified: 2+ layers 2)^ muscle 3)^ connective:
extensive matrix. eg, blood, bone, lymph, cartilage, etc.4)^ nervous the 4 types combined can form an organ, difforgans combine into a “system.”key to MCAT Bio is knowing that body isentire organism with systems that work inconjunction w/ eachotherIntercellular Communicationoccurs via 3 types of mol’s1) neurotransmitters (nervous system)2) local mediators (paracrine system)
-released into interstitial fluid-act on neighboring cells mm away-eg, prostaglandins,
Æ^ smooth
muscle contraction, inflammationaspirin inhibits this.
- hormones
(endocrine system)
they differ mainly by distance traveled.NT’s travel over short intercellular gaps orsynapseslocal mediators function in immediate areaaround cellhormones travel through the organism via thebloodstreamNT tends to be rapid, direct, and specifichormonal tends to be slower, spreadthroughout the body, and affect many cells andtissues in many ways.Nervous systemrapid and direct communication b/w specificparts of body Æ^ muscular contractions or glandularsecretionsincludes: brain, spinal cord, nerves, neuralsupport cells, organs such as eye and ear.main unit is neuron-electrical signal from one cell viaelectrochemical means. so specialized itcannot divide. depends entirely on glucose.depends on aerobic respiration: low stores ofglycogen and oxygen, so relies heavily onblood. usually soma (body) and 1 axon w/many branches, as well as many dendrites.dendrites receive signal to be transmittedelectrical stimulus goes to axon hillock, ifgreat enough, hillock generates AP towardssynapse, which passes signal to cell.Basic anatomy of neuron:
dendrites, nucleus, axon hillock,mitochondrion in soma. nodes of ranvier,myelin sheath, axon terminal.Neurons do NOT depend on insulin to obtainglucose. Get it right from the blood.Action PotentialAP is disturbance in e-field across membraneresting potential – established by anequilibrium b/w passive diffusion across themembrane and Na+/K+ pump. it moves 2 +charged K+ ions into cell while 3+ Na+ ionsout of cell. force pushing Na back into clelbecomes greater. at equilibrium, inside membhas _ potential difference (voltage) comparedto outside. called resting potential.voltage gated sodium channels – allow Na+ toflow thru membrane shortly. the membranereverses polarity. Depolarization. Neuronalmembrane also contains voltage gatedpotassium channels. cause repolarization.hyperpolarization. passive diffusion returnsmembrane to resting postential. throughout,sodium-potassium pump keeps working. AP Overview 1) Membrane at rest. Na/K channels closed2) Na channels open, cell depolarizes3) K channels open as Na channels begin to
close
- Na channels closed. Open K channelsrepolarize membrane5) K channels close and membraneequilibrates to resting potentialAP is all or nothing. Membrane completelydeporalirzes or no AP is generated. must passa threshold stimulus. Once there is AP,absolute refractory period until another AP canhappen.Aps, besides in neurons, also in skeletal andcardiac muscle.Neural impulses transmitted intercellularly viaa synapse. Usually chemical, not electrical.aka motor end plate if neuron-muscle connexunidirectional. small vesicles filled with NTreside just inside presynaptic membrane.membrane near end contains large number ofCa2+ voltage gated channels. When AParrives, these are activated to allow calciumflow into cell. causes NT vesicles to bereleased through exocytotic process intosynaptic cleft. diffuses across cleft withrandom or “Brownian” motion.
Post synaptic
membrane contains NT receptor proteins.When attached, post syn membrane becomesmore permeable to ions. ions move throughnow permeable proteins called ionophores,completing transfer of neural impulse.NT attaches to receptor only for milisecond.then released back into syn cleft. if remains,can stimulate post syn memb over and over. todeal with this, cell can use enzyme to destroyNT. it can also be absorbed by cell…Usually 1 NT per 1 synapse. Can either inhibitor excite. Some have diff effects dependingon area;-Acetyl Choline (ACh)on heart: inhibitory effecton visceral smooth muscle (intestines):excitatoryReceptors-ion channels themselves, or,nd^ -2^ messenger systemFor prolonged change, eg, memory, 2
nd
messenger preferred. G proteins
initiatie 2
nd^ messenger systems
-attached to receptor inside post syn memb.-when receptor stimulated by NT, part of the Gprotein called alpha subunit breaks free Alpha subunit may 1) activate separate specific ion channels2) activate a 2
nd^ messenger, eg, cAMP or GMP
- activate intracellular enzymes4) activate gene transcription.overall: chemical synapse most important.slowest step in txfer of nervous signal, canonly occur in 1 direction. 2
nd^ messenger also
important to recognize.Support Cellsnervous tissue contains glia cells/neuroglia.usually ratio of 10::1 glia to neuronsneuroglia, unlike neurons, CAN divide, andusually do during traumatic brain injury to fillany space created in CNS.6 types of glia- microglia
- phagocytize microbes and debris in CNS- ependymal - epithelial that line the cerebral fluid containing parts of CNS- satellite - support ganglia in PNS - astrocytes - star shaped neuroglia in CNS, give physical support to neurons, helpmaintain mileu- oligodendrocytes –
wrap around axons in
CNS, creating electrical insulation.-neurolemmocytes or
Schwann
. – in PNS,
increases rate at which axon can txmit signals
only vertebrates have mylenated axonsto naked eye: White matter
- mylenated axons Grey matter
- neuronal cell bodies. nodes of ranvier
allows for saltatory conductionStructure of Nervous SystemNeurons are of 3 functions1)^ Sensory (afferent)
receptor cell from environment. txfers signalto other neurons. 99% is discarded by brain.Located located dorsally (toward back) fromspinal cord.2)^ Interneurons –
txfers signals from neuron
to neuron. 90% of neurons in body3)^ Motor (efferent) neurons –
carry signals to
muscle or gland called “effector”. Locatedventrally (toward front) from spinal cordThink of CNS as brain + spinal cord, PNS aseverything else.CNS integrates nervous signals b/w sensoryand motor neurons. connected to peripheralparts of body via PNS. PNS handles sensoryand motor functions of nervous system.Simple reflex arcreceptor
Ædorsal root ganglion
Æsensory
neuron
Æ^ interneuron
ÆMotor neuron
Æ
effectorPNS divides to- Somatic nervous system
environement. motor neurons only innervateskeletal muscle. cell bodies of these in ventralhorns of spinal cord. use ACh for NT.considered “voluntary.” sensory bodieslocated in dorsal root.- Autonomic nervous system
(ANS) – sensory
receives singals from viscera, organs insideventral body cavity. function is involuntary.NT used by all preganglionic neurons and bythe post ones in the parasympathic is ACh.The post ganglionic in the symp system useeither epinephrine (adrenaline) ornorepinephrine (noradrenaline).divides into 2 antagonistic systems:- sympathetic (fight or flight): activates heart, major skeletal muscles, dilatespupils for night hunting, redirects blood, etc.eg, heart, it increases beat rate, stroke volume,constricts vessels around digestive andexcretory systems to increase flow aroundskeletal muscle.signals originate in spinal cord. if in CNS,called nucleus, if outside CNS, called ganglion- parasympathetic (rest and digest)
deactivates all of the above and activatesintestines and excretory system.eg, slows heart rate, increases digestive andexcretory activity.receptors for epi and norepi called
adrenergic
receptors for ACh called
cholinergic
2 types- nicotinic
: generally found in postsyn cells of synapse between ANS pregang and post gangneurons, and on skeletal membranes atneuromuscular junction.- muscarinic
: found on effectors of PNS. Overview: ANS is involuntary. innervatescardiac and smooth muscle, some glands.somatic nervous system innervates skeletalmuscle. Autonomic pathways controlled byhypothalamus.Generally, when you hear acetylcholine
Æ^ somatic and parasympathetic nervous systems (nor)epinephrine
Æ^ sympathetic nervous
systemCentral Nervous Systemspinal cord, lowerbrain, all of higher brainacts mainly as conduit for nerves to reachbraindoes limited integrating functions-walking reflexes, leg stiffening, etc. lower brain
: medulla (pons, mesencephalon), hypothalamus, thalamus, cerebellum.Integrates subconcious activities such as respsystem, arterial pressure, salivation, emotions,and rxn to pain, pleasure. higher (cortical) brain
: incapable to function
w/o lower brain. acts to store memories,process thoughts. consists of cerebrum/cortex.Sensory Receptorsoverall: sensory receptors transduce physicalstimulus to neural signals5 types of sensory receptors-mechanoreceptors (touch)-thermoreceptors (change in T)-nocireceptors (pain)-e-magnetic (light)-chemoreceptors (taste, smell)on MCAT, prob just deal with eye and ear.Eyemight show up as physics passage. understandlens of eye is converging, flatting the eye byrelaxing ciliary muscles makes the lens lesspowerful, thus moving focal point away fromlens.
let’s follow path of light through eye.light reflects off object in external environ,strikes first on cornea (nonvascular, made ofcollagen). refractive index of abt 1.4, bendingof light occurs at interface of air and cornea,not lens. Æ^ goes to anterior cavity/aq. humor. (leaksout to canal of Schlemm. if blocked,glaucomma, blindness.)from ant. cavity, light enters lens. ciliarymuscle attached to it. circles lens. when itcontracts, opening of circle decreases,allowing lens to be more like sphere, bringingfocal point closer to lens. when relaxes, lensflattens, increasing focal distance.eye acts as converging lens. object is outsidefocal distance, image on retina is real andinvertedRetina covers inside of back/distal part of eyecontains rods and cones. tips of these containpigments, chem change when e-trons struck byphoton. rods –
rhodopsin pigment. made from protein retinal. derived from vit A. photon isomerizesretinal, causing membrane of cell to be lesspermeable to Na+, causes hyperpolarization.transduced into neural action potential, signalsent to your noggin. sense wv 390nm to 700.cannot distinguish colors. cones –
distinguish 3 types of colors. fovea- small point on retina containing mostcones. vwhere vision is most acute. iris : colored portion of eye, creates openingcalled
pupil
. made of circular+radial muscles in dark, symp ns contracts, dillating, allowmore light in.in light, parasymp contracts muscles,constricting pupil, ,screening out light.The Earcan show up on physics passage, concerningwaves or mechanics. Know cochlea detectssound, while semicircular canals detectorientation/movement of head.3 basic parts1)^ outer ear:
cartilage, helps direct sound into external canal. carries wave to tympanicmembrane / ear drum / begin of middle ear2)^ middle ear:
malleus, incus, and stapes (bones). act as lever system, translate wave tooval window. increase in force. increase in
pressure since oval window is smaller than eardrum. (physics, mech advantage).3)^ inner ear:
wave moves thru cochlea to center of spiral, spirals back out to roundwindow. as wave moves thru cochlea, thealternating increase/decrease of P movesvestibular membrane in and out. movementdetected by hair cells of organ of corti,transduced into neural signals towards brain.also here are semicircular canals, responsiblefor balance (contain fluid and hair cells).responds to gravity. senses motion.Nose and Mouthsenses called olfactory and gustatory.4 tastes1)bitter2) sour3) salty4) sweetall tastes are combo’s of the above.
3)^ flow
- shedding of uterine lining for ~ 5daysin menstrual cycle, all of FSH, LH, andEstrogen peak right before ovulation.Estrogen and progesterone have peaks duringsecretory phase.Fertilization and Embryologyonce in fallopian, egg swept towards uterus bycilia. fertilization normally takes place infallopian tube.sperm entry into egg causes cortical reaction,preventing other sperms from fertilizing.NOW
oocyte
goes thru second meitotic division to become
ovum
, releases 2
nd^ polar
body. fertilization occurs when nuclei ofovum and sperm fuse to form
zygote
cleavage
beings while zygote still in fallopian Æ^ many cycles of mitosis. when 8 or morecells, called
morula
. cells here are
totipotent
or can express any gene.Form hollow ball called
blastocyst
. lodges in
uterus in process called implantation about 7days after ovulation. egg begins secretingpeptide hormone
human chorionic gonadotropin (HCG).
prevents degeneration
of corpus luteum, maintains its secretion ofestrogen and progesterone. HCG in blood andurine of mother a sign of pregnancy. placenta
is formed from tissue of egg and mother, takes over job of hormone secretion.starts secreting its own estro and progest.After 8 cells, embryo starts to
differentiate
committed developmental path – determination
gastrulation forms
gastrula
nd in 2 week.
primitive streak
formed in mammals,
analagous to
blastopore
in aquatic vertebrates.
cells destined to become mesoderm migrate toprimitive streak. 3 germ layers formed:1)^ ectoderm
- outer coverings, skin, nails, tooth enamel, cells of nervous system andsense organs.2)^ mesoderm –
the stuff that lies between inner and outer coverings of body: muscle,bone, all the rest. 3)^ endoderm –
lining of digestive tract, most of the liver and pancreas.
rd^ in 3 week, gastrula
Æ^ neurula (neurulation).
notochord induces overlying ectoderm tothicken and form into nerual plate. Eventuallydegenerates, while a neural tube forms fromneural plate to become spinal cord, brain, andmost of nervous system. (Induction is whenone cell type affects direction of differentiationof another cell type).Part of normal cell development is
apoptosis
programmed cell death.essential for development of nervous system,operation of immune system, and destructionof tissue b/w fingers and toes to create normalhands and feet. failure to do this
Æ^ cancer
This is regulated by protein activity instead oftranscription/translation level. Mitochondriaplays important role. Proteins for apop arepresent but inactive in healthy cell.
Overview of Hormones^ Anterior Pituitary hGH^
- Growth of nearly all cells ACTH
- stimulates adr. cortex FSH^
- grwoth of follicles (F); sperm prod (M) LH^ – causes ovulation; stims estro, testost
secretion TSH^
- stims release of T3 and T4 in thyroid Prolactin
- promotes milk production^ Posterior Pituitary Oxytocin
- milk ejection, uterine contraction ADH
- water absorption by kidney;
↑^ Hb Hg
Adrenal Cortex Aldosterone
-^ ↓Na excretion;
↑K excretion;
Blood Hg. Cortisol
-^ ↑^ blood levels of carbs, proteins, fats
Adrenal Medulla Epinephrine
- stimulates sympathetic actions Norepinephrine
- stimulates sympatheticactions Thyroid
T3, T
-^ ↑basal metabolic rate Calcitonin -^ ↓blood calcium^ Parathyroid PH^ –^
↑^ blood calcium
Pancreas Insulin
- Promotes entry of glucose into cells, ↓glucose blood level Glucagon - Increases gluconeogenesis, ↑blood glucose levels
Ovaries Estrogens
- growth of F sex organs, LH surge Progesterone
- prepares, maintains uterus forpregnancy Testes Testosterone
- 2ndary sex characteristics,closing of epiphyseal plates Placenta HCG
- stimulates corpus luteum to grow,release estro and progest Estrogens
Progesterone
- “ “ to a lesser extent Digestive and Excretory Systems Digestion
: breakdown of ingested foods bfore absorbed into body. major rxn formacromolecules is hyrdrolysis.anatomy of digestive tract:mouth
Æ^ esophogous
Æ^ stomach
Æ^ small
intenstine (duodenum, ileum, jejunum)
Æ
large intestine (ascending colon, transversecolon, descending colon, sigmoid colon)
Æ
rectum
Æ^ anus. Digestion begins in mouth w/
α-amylase
Starch is major carb in human diet. breaksdown long straight cahins intopolysaccharides. Chewing increases surfacearea of food, enables more enzymes to act on itat once. Form a bolus of food. Pushed intoesophogous by swallowing and then downesophogous via peristalsis. performed bysmooth muscle. no digestion in esophagus.StomachAll digestion, no absorption.bolus enters stomach at cardiac sphincter. stomach
: flexible pouch that stores and mixes food, reducing it to semifluid mass called chyme.
Has^ exocrine glands
with gastric pits.
another function of stomach: begin proteindigestion with pepsin. low pH assists processby denaturation. full stomach has pH of 2.Helps kill ingested bacteria. 4 types of cells:1)^ mucous cells –
secrete mucous to line
stomach wall and necks of exocrine glands.food can slide along wall without damage,protects epithelial lining from acidicenvironment. also secrete a little pepsinogen.2)^ chief (peptic) cells –
found deep in
exocrine glands. secrete
pepsinogen
, the
zymogen precursor to
pepsin
. activated to
pepsin by low pH. Once activated, beginsprotein digestion.3)^ parietal (oxyntic) cells –
secrete
hydrochloric acid (HCl) which diffuses tolumen. needs lots of energy to do this. CO2involved, making carbonic acid inside cell.H+ ion expelled to lumen, while bicarbonateion expelled to interstitial fluid side. net result
lower pH of stomach and raised pH of blood.also secrete intrinsic factor, helps ileum absorbB12.4)^ G cells
- secrete gastrin to interstitium. large peptide hormone, absorbed into bloodand stimulates parietal cells to secrete HCl. major hormones that affect secretion ofstomach juices: -acetylcholine:
↑^ all types of secretion -gastrin:
↑^ HCl mostly -histamine:
HCl mostly Small Intestine90% of digestion and absorption. 3 partslargest to smallest:
duodenum
,^ jejunum
ileum
. Most digestion in duodenum, most absorption in the other two.
small intestine
wall contains
villi^ – finger like projections. on apical surface of the cells of each villus cell(enterocytes) are much smaller finger lengthprojections,
microvilli
. fuzzy covering, aka
brush border
. Contains membrane bound digestive enzymes for carbs, as well asdextrinase maltase sucrase and lactase;peptidates for proteins, nucleosidases for n-tides. Some epithelial are
goblet cells
, secrete
mucus to lubricate intestine. Lots of cell deathand growth here. villus : capillary network and lymph vessel called
lacteal
. Nutrients absorbed pass thru cappilary and then lacteal.intestinal exocrine glands deep in villi. secretepH 7.6 juice and lysozyme (regulates bacteria).Pancreas chyme
squeezed out of stomach thru
pyloric
sphincter
into duodenum. pancreas has sent bicarbonate, so pH is ~6.Panc also acts as exocrine gland, releasingenzymes from acinar cells thru panc. duct intoduodenum. Major panc. enzymes: - trypsin
: proteins
Æ^ small polypeptides
hyrdolyzes polysacch’s
to disacch’s and tri’s. much more powerfulthan salivary.- lipase-
degrades fat, spef. triglycerides. fat is insoluble in aq. soln. reduced surface areaunless bile breaks it up. bile produced in liver,stored in gall bladder. released thru cysticduct, empties into common bile duct shared w/liver.^
Æ^ pancreatic duct
Æ^ duodenum.
Bile
emulsifies fat, contains bilirubin, changing it
physically but not chemically. increasessurface area, allowing lipase to break downinto fatty acids and monoglycerides.- ribonuclease - - deoxyribonuclease chyme is moved thru intestines by peristalsis.segmentation is mixing of chyme w/ digestivejuices.The Large IntestineIf get a large intest question, think waterreabsorption. profuse water loss in diarrhearesults from problem in the LI. knowmutualistic symbiosis b/w humans andbacteria there. bacteria get leftovers, we getvitamins4 parts:1) ascending colon2) transverse colon3) descending colon4) sigmoid colonmajor functions: water abs and electrolyte absif this fails
Æ^ diarrhea. LI also has E.Coli. they produce vitamins K, B12, thiamin,riboflavin. healthy feces has 75% water. restis dead bacteria, fat, inorganic matter, etc.Gastrointestinal Hormonesdon’t need to know them but may appear. justunderstand idea of digestion. body eats to gainenergy in form of food. digestive systembreaks down food so it can be absorbed intobody. one prob is that food may move to fastand come out undigested. stomach storesfood, releases small amnt at time to bedigested / absorbed by intestine. that waybody can take in large amnt at a single timeand take a long time to digest. GI hormonesjust help to regulate this process. secretin
- responds to HCl in duodenum. cholecystokinin
- responds to food in duodenum gastric inhibitory peptide - responds to fat /
protein in duodenum.Absorption and Storage overviewconvert ingested food into basic nutrients thatsmall intestine is able to absorb. onceabsorbed into enterocytes, nutrients processedand carried to indiv. cells for use. Quick anddirty overview of the 3 main nutrients, carbs,proteins, fats… Carbohydrates –
80% glucose. absorbed via
2ndary actie transport down conc. gradient ofsodium. all absorbed into bloodtream andcarried by portal vein to liver. liver’s job is tomaintain constant blood glucose level. liverconverts the carbs to glucose and thenglycogen, breaks down when needed.
when glycogen stores are full, glucose isconverted to fat for long-term storage. For bigpicture, think about glycolysis and kreb’scycle. Proteins –
virtually all dietary protein is broken down completely into aa’s before beingabsorbed into blood. When you hear proteins,think “nitrogen.” Uses cotransportmechanism.ammonia is by-product of gluconeogenesisfrom proteins. nearly all NH3 converted tourea by liver and then excreted in urine bykidney. Fats: fat is insoluble in water, so needs carrier, such as albumin (a lipoprotein). hear “fat”think “long-term energy storage, lots ofcalories (energy) with little weight.most dietary fat consists of triglycerides.shuttled via bile micles to brush border of sm.intestine. energy rate (cal per gram)Fat > carbs > protein but takes diff amnt of energy to break downglobules called
chylomicrons
move into
lacteals
of the
lymph
. emptied into large veins
at throactic duct. from adipose, most fa’stransported as free fa, which combinesimmediately in blood w/ albumin.The Liverpositioned to receive blood from capillary bedsof intestines, stomach, spleen, and pancreasvia^ hepatic portal vein
. leads eventually to
vena cava.Functions: Blood storage
: liver can expand to act as Hb reservoir for body Blood filtration
: kupfer cells phagocytize bacteria picked up from intestines Carbohydrate metabolism
: liver maintains
normal blood glucose levels thrugluconeogenesis, glycogenesis, and storage ofglycogen. Fat metabolism
: liver synthesizes bile from cholesterol and converts carbs, proteins intofat. oxidizes fa’s for E, forms mostlipoproteins. Protein metabolism
: liver deaminates aa’s,
forms urea from NH3 in the Hb, synthesizesplasma proteins such as fibrinogen,prothrombin (important clotting factors)albumin (major osmoregulatory protein in Hb),and most globulins (group of proteins andantibodies), and synthesizes nonessential aa’s. Detoxification
: detoxified chemicals excreted by liver as part of bile or polarized so may beexcreted by kidney.
Erythrocyte destruction
: Kupfer cells also
destroy irregular erythrocytes. Mostly done byspleen. Vitamin storage
: liver stores vitamins A, D,
and B12. also stores iron combining withprotein apoferritin to form ferritin.when liver metabolizes fat for E, producesketone bodies.
Æ^ ketosis / acidosis. when liver metabolizes fat orprotein for energy, bloody acidityincreases
↓pH.
The Kidney 3 functions: 1) excrete waste: urea, uric acid, NH3, PO3.2) maintain homeostasis of body fluid V,solute composition.3) control plasma pH.2 kidneys. each is made up of
outer cortex
and^ inner medulla
. Urine created by kidney
and emptied into the
renal pelvis
. emptied by
ureter
, which caries urine to
bladder
, drained
by^ urethra
nephron
: functional unit of kidney. blood flows first into capillary bed of nephron called glomerulus
.^ Bowman’s capsule
and
glomerulus make up the
renal corpuscle
Hydrostatic pressure forces some plasmathrough
fenestrations
of golmerular
endothelium and into Bowman’s capsule.fenestrations screen out blood cells and largeproteins from entering the capsule. fluidentering is called
filtrate
. moves to
proximal
tubule
. where
reabsorption
takes place.
2ndary active transport proteins on apicalmembranes of prox tubule cells, reabsorbnearly all glucose, most proteins, and othersolutes. transport proteins become saturateduntil reach
transport maxiumum
. any more
solute washed into urine. some solutesreabsorbed by passive or facilitated diffusion.Water is rabsorbed into renal interstitium ofprox tubules across relatively permeable tightjunctions down the osmotic gradient.drugs, bile, uric acid, antibiotic, toxins, othersolutes
secreted
into filtrate by
proximal
tubule
. H ions secreted thru antiport system w/ Na.
Æ^ net result: reduce amnt of filtrate in nephron w/o changing osmolarity.from prox tubule, filtrate flows into
loop of
Henle
. loop dips into medulla. function is to increase solute concentration and thus osmoticpressure of medulla. water passively diffusesout of loop of Henle and into medulla.descending loop has low permeability to salt,so filtrate osmolarity goes up. as filtrate risesout of medulla, salt diffuses out of ascending
loop, passively at first, then actively.ascending loop is nearly impermeable towater. 2
nd^ capillary bed called vasa recta surround loop and helps to maintain [ ] inmedulla. Distal tubule
: reabsorbs Na+ and Ca2+ while secreting K+, H+, and HCO3-. Aldosteroneacts on distal to increase sodium andpotassium memb transport proteins. Neteffect: lower filtrate osmolarity.
collecting
tubule
: at end of the distal, ADH acts on it to increase permeability to H20.
Æ^ more
concentrated filtrate.
empties into
collecting
duct. cd carries filtrate into highly osmoticmedulla. impermeable to water, but sensitiveto ADH. if ADH, permeable to water, urine ismore concentrated.
Æ^ renal calyx
Æ^ renal
pelvis.Juxtaglomerular Apparatus-monitors filtrate pressure in distal tubule.- granular cells
secrete
renin
Æ^ initiates regulatory cascade of angiotensinsI, II, and III.
Æ^ adr. cortex secretes aldosterone.
Æ^ distal tubule forms proteins to absorb sodium and secrete potassium.ADH = “Always Digging Holes” in thecollecting duct. Overview
: know function of each section of the nephron: filtration occurs in renalcorpuscle; reabsorption and secretion mostlyin proximal tubule; loop of Henle concentratessolute in medulla, distal tubule empties intothe collecting duct; collecting ductconcentrates urine. Amnt of filtrate is relatedto hydrostatic pressure of glomerulus.Descending loop of henle is permeable towater, and ascending loop is impermeable towater and actively transports sodium intoKidney.big picture: function of kidney is homeostasis.--------------------------------------------------------Cardiovascular Anatomyconsists of heart, blood, and blood vessels.for MCAT, must be able to trace circulatory path of blood
left ventricle, pumped through aorta. fromaorta, branch with many smaller arteries,which branch into still smaller arterioles,which branch into still smaller capillaries.collected into venules, which themselvescollect into larger veins, which collect againinto superior and inferior vena cava. the venacava empty into the right atrium of the heart.
systemic circulation – 1
st^ half.
from right atrium, blood squeezed into rightventricle, r ventr pumps blood throughpulmonary arteries to arterioles to capillariesof lungs. from lung capillaries, blood collectsin venules, then veins, finally in pulmonaryveins leading to heart. pulmonary veins emptyinto left atrium, which fills left ventricle. 2
nd
half of circulation is called pulmonarycirculation. Closed circulatory system forhumans.concentrate on function: left v contracts w/ themost force to propel the blood throughsystemic circulationHeart is large muscle. Not attached to bone. Systole
occurs during contraction;
diastole
during relaxation of entire heart, and thencontraction of atria.Blood is propelled by hydrostatic pressurecreated by contraction of heart. Rate ofcontractions controlled by ANS. Not initiatedby ANS, though. Contracts automatically byspecialized cells called
sinoatrial node (SA
node)
located in R atrium.
spreads
contractions to surrounding muscles viaelectrical syapses via
gap junctions
. SA pace
is faster than normal heartbeats but parasymp vagus
innervates SA node, slowing contractions. AP generated by SA nodesspreads around both atria causing them tocontract and spread to
AV note
. AV is slower
to contract. from AV node, moves to
bundle
of His
(on wall separating ventricles). spread to^ Purkinje fibers
. AP is spread through
muscle.must know the vagus nerve. parasympathetic,innverates heart and digestive system. slowsrate of heart contractions and increaesdigestive activity of enzymes. Know role andlocation of purkinje fibers. Arteries
: elastic. stretch as fill w/ blood. when ventricles fully contract, stretchedarteries recoil. smooth muscle; innervated bysympathetic nervous system. Epinephrine
: powerful vasoconstrictor causing narrowing of arteries.Medium-sized arteries constrict undersympathetic stimulation; large ones lessaffected. Arterioles
: very small. Wrapped by smooth muscle. constrict/dilate to regulate bloodpressure, also rerouting.
defined by the A and B surface antigens. iftype A, then you don’t make A antibodies, ofcourse. Type O has neither A nor B antigens,but makes both A and B antibodies. Blooddonor may only donate to an individual thatdoes not make antibodies to donors blood. Omay donate to anyone; individual with ABmay receive from anyone.Genes that produce A and B antigens arecodominant.
Type O is 2 recessive alleles. A or B may be hetero or homozygous. Rh factors
: surface proteins on red blood cells. Rh-negative or Rh positive. usuallymild w/ transfusions. Important duringpregnancy of an Rh-negative mother with Rh-positive fetus. 1
st^ pregnancy, mother not exposed to fetal blood until birth. but by 2
nd
birth, has developed imune response. Canattack baby if not caught early.^ Muscle, Bone, and Skin Muscle3 types of muscle tissue:1) skeletal2) cardiac3) smoothmuscle contraction has 4 possible functions:1) body movement2) stabilization of body position3) movement of substances thru body4) generating heat for homeostatisSkeletal Musclevoluntary muscle tissue; can be consciouslycontrolled. connects one bone to another.attaches to the
tendon
attached to the bone.
usually stretches across a joint.Muscles work in groups, antagonistic
- the^ agonist contracts - the^ antagonist stretches example: upper arm muscle – biceps andtriceps.OR synergistic
-movement / posture. ligaments
connect bone to bone.
shivering
- involuntary skeletal movement controlled by hypothalamus to generate heat.Physiology of Skeletal Muscle Contraction sarcomere
: smallest functional unit. composed of many strands of 2-proteinfilaments,
thick and thin
. surrounded by
endoplasmic reticulum of muscle cell called sarcoplasmic reticulum.
with Ca2+ ions. lots of mitochondria, nuclei.skeletal muscle is
multinucleate.
sarcolemma
wraps several myofibrils together to form amuscle cell or muscle fiber. many fibersbound into fasiculus, fasiculae into singlemuscle.Know that during contraction, H zone and Iband get smaller, while A band does notchange size.thick filament of sarcomere made up of myosin.
globular heads protrude along both ends of thick filament. thin filament is mostlyglobular protein
actin
. attached are troponin
and tropomyosin.Myosin and actin work together slidingalongside to make contractile force of muscle.Each^ myosin head
crawls in
5 stage cycle.
- tropomyosin covers active site on actin;prevents myosin head from binding. myosinhead remains “cocked” in high-energy positionwith phosphate and ADP attached.2) Presence of Ca2+ ions: troponin pullstropomyosin back, exposing active site, allowsmyosin head to bind to actin.3) Myosin head expels phosphate and ADPand bends into low-E position, dragging actinwith it. called “power stroke” bc of shorteningof sarcomere and muscle contraction.4) ATP attaches to myosin head, releasing itfrom active site, which is covered immediatelyby tropomyosin.5) ATP
Æ^ PO3 + ADP
Æ^ causes myosin head
to cock into high-E position.Cycle repeats many times to form acontraction.
Ca2+ is important. muscle contraction begins with AP. neuronattaches to muscle cell:
neuromuscular
synapse.
AP of neuron releases ACh into cleft. activates ion channeles in sarcolemmaof muscle cell creating AP. AP moves deepinto muscle cell via small tunnels in membranecalled
T-tubules.
allows for uniform
contraction by allowing to AP to spread morerapidly. AP spreads to sarc retic, allows inCa2+ ions. begin 5 stage cycle. at the end ofthe cycle, Ca2+ is “reuptaken” by sarc retic.A Motor Unit
fibers thruout muscle innervated by singleneuron.neuron + fibers =
motor unit
smaller mu’s react quicker than large ones.smooth motion works via this process.fingers: small mu’s, intricate movementback: large mu, large forceSkeletal Muscle Type3 types:1)^ slow oxidative
(type I) fibers. “slow
twitch”. Red. large amounts of
myoglobin
(O2 storing protein similar to Hb, but can onlystore one molecule of O2.) lots ofmitochondria. slow at splitting ATP. slow tofatigue, but slow to contract.2)^ fast oxidative
(type IIA) fibers. “fast
twitch.” also red. split ATP at high rate.contract rapidly, not as resistant to fatigue asslow.3)^ fast glycolytic
(type IIB) fibers. “fast
twitch B.” low myoglobin. appear white.contract rapidly, lots of glycogen.Most muscles in body mixture of these 3.Depends where… Posture muscles mostly typeI. type IIA in legs. type IIB in upper arms.Adult human skeletal muscle: so specializedthey don’t do mitosis. Instead, they changedue to force. including: diameter of musclefiber^ ↑
, number of sarcomeres and mitochond ↑, sarcormeres’ length
↑. Changes referred to
as hypertrophy.Cardiac Muscleheart: mostly cardiac muscle. striated,composed of sarcomeres. Each cell only 1nucleus. separated from others by intercalateddisc (contain gap junctions, allowing AP tospread via synapse). mitochondria of cardiaccell much larger and more numerous thanskeletal.
also, not connected to bone. forms a net, contracts upon itself like squeezing fist.-involuntary-grows via hypertrophy-AP has plateau after depolarization Æ^ caused by Ca2+ entry from voltage gatedchannels.Smooth Musclemostly involuntary. innervated by ANS. likecardiac, only 1 nucleus. thick and thinfilaments, but not organized into sarcomeres.contain intermediate filaments, connected todense bodies. when contract, causeintermediate filaments to pull dense bodiestogether. smooth muscle cell shrinks length-wise.2 types of smooth muscle:
1)^ single-unit
: visceral. most common smooth
muscle. connected by gap junctions, spreadingof AP. cells can contract as single unit. foundin small arteries and veins, stomach, intestines,uterus, urinary bladder. many cells innervatedby 1 neuron.2)^ multi-unit
: each multiunit muscle fiber attached directly to a neuron. 1 cell, 1 neuron.group of fibers can contract independently.large arteries, bronchioles, iris, etc.Also contract/relax in presence of hormones,changes in in pH, O2, CO2 levels, T, ionconc’s.Boneliving tissuesupports soft tissue, proects internal organsassists in movement of body, minteral storage,blood cell production. energy storage, too:adipose in bone marrow.4 types of cells surrounded by matrix:1)^ Osteogenic/Osteoprogenitor
cells:
differentiate to osteoblasts2)^ Osteoblasts
: secrete bone-forming collagen. –incapable of mitosis. differentiateinto osteocytes as they release matrix aroundthemselves.3)^ Osteocytes
: also incapable of mitosis. E/x nutrients and waste w/ blood4)^ Osteoclasts
: reabsorb bone matrix, releasingminterals back to blood. Develop from WBCcalled monocytes. Spongy bone
- contains red bone marrow, site of RBC development (homopoiesis). Compact bone - surrounds medullary cavity, holds yellow bone marrow. contains adipose.highly organized. Compact bone
remodeling process
osteoclasts burrow tunnels, called
Haversian
canals. Osteoblasts then lay down new matrixfofrming concentric rings,
lamellae
Osteocytes exchange nutrients via canaliculi.H canals contain blood and lymph vessels,connected by crossings called
Volkmann’s
canals
. Entire system of lamellae and H canal called “osteon.”Bone Function in Mineral HomeostasisCa salts mostly insoluble. usually bound toproteins in blood. Free Ca2+ in blood isimportant concentration. too much
: membranes hypo-excitable
Æ
lethargy, fatigue, memory loss too little
: cramps and convulsions.
Most calcium stored in bone matrixashydroxyapatite.Bone Types and Structure4 types: long (finger, arm), short (ankle orwrist), flat (skull, ribs, made of spongy bone),or irregular.Bone is not just for support, protection, andmovement. Also stores calcium andphosphate, maintains their concentrations inblood. Stores energy in adipose. Also, site ofblood cell formation.Cartilageflexible, resilient, connective tissue. mostlycollagen. great tensile strength. no bloodvessels or nerves except in outside membranecalled perichondrium.3 types: 1) hyaline 2) fibrocartilage 3) elastichylaine most common. reduces friction andabsorbs shock in joints.Joints3 types1)^ Fibrous
- b/w 2 bones closely/tightly together. little or no movement. eg skullbones or teeth w/ mandible2)^ Cartilaginous
: - also restricted movement.
b/w 2 bones connected by cartilage,ribs/sternum, eg.3)^ Synovial
: not bound directly by innervating cartilage. separated by capsule filled w/synovial fluid. allows lubrication andnutrients to cartilage. also has phagocytic cellsthat remove microbes from wear/tear. allowfor lots of
movement
Skinconsidered organ. group of tissues workingtogether.
FUNCTIONS:
1)^ Thermoregulation
: blood conducts heat to
skin. hairs excreted and can trap heat. skinhas warmth and cold receptors.2)^ Protection
: physical barrier against bacteria, dehydration chemicals, UV rays3)^ Environmental Sensory Input
: skin
gathers info from environment. sense T, P,pain and touch.4)^ Excretion
: water and salts excreted. 5)^ Immunity
: specialized cells of epidermis are components of immune system. besidesbeing a barrier.6)^ Blood reservoir
: vessels in dermis hold
10% of our blood.7)^ Vitamin D synthesis
: UV rays activate
molecule in skin that is precursor to vit D.modified by enzymes in liver and kidneys tobecome the vitamin.
2 PARTS
1)^ epidermis
: avascular epithelial. made up of
keratinocytes for waterproofing. melanocytesfor melanin (pigment). Langerhans forinteraction with helper T cells of immunesystem. Merkel cells attach to sensory neuronsfor sensation of touch. 5 strata deepest layer is Merkel cells and stem cells.continually divide to produce keratinocytesand others. Keratinocytes rise to the top layer.as they rise, accumulate keratin and die, losingcytoplasm and nucleus, etc. at top layer,slough off and die.
2-4 week process.
pressure or friction stimulates thickeningcalled callus.2)^ dermis
fat beneath skin important insulator for body.connective tissue from mesoderm. embeddedby Hb vessels, nerves, glands, hair folicles.collagen and elastic fibers
Æ^ strength.
Meissner’s corpuscle – touchsebaceous gland – oilPacinian corbuscle – vibration Populations Mendelian ConceptsMendel, monk, crossed purple flowered plantsw/ white flowered.
first filial, F1, produced
purple flowers.
Æ^ purple dominant, white recessive. 2
nd^ generation had mendelian ratio of 3:1 dominant to recessive. test cross
- Mendel crossed unknown purple F1 w/ homozygous recessive (white) parent.White offspring of this proved F1 washeterozygous phenotype - expression of trait genotype - genetic makeup complete dominance
: two homologous
chromosomes. corresponding genes @ samelocus on respective chromosomes.(homozygous dominant) When there is noblending of dominant and recessive. partial / incomplete dominance
dominant and recessive. codominant
- both traits exhibited. Each gene contributes to an allele to genotype.
1 dominant + 1 recessive = heterozygous =“hybrid” st^ (1^ ) Law of Segregation –
alleles segregate
independently when forming gametes. 50%chance of possess any allele. Inbreeding
: what mendel did. does not change %’s of alleles but causes homozygotes ↑ Outbreeding
is mating of nonrelatives
Æ
heterozygotes
Punnett square
- predicts genotypic ratios. dihybrid crossWw+Gg x Ww+Gg
Æ^ 9 y, r3 y, w
“dihybrid cross”
3 g, r1 g, w
9:3:3:1 = phenotypic ratio of dihybrid cross nd (2^ ) Law of Independent Assortment
genes on diff chromosomes assortindependently. closer genes are on achromosome, more likely they will staytogether.male vs. female chromosomesrd^23 pair establishes sex of individual.aka “sex chromosome”The pair of sex chromosomes appear as an Xand a Y. If found on either, gene consideredsex-linked. woman is carrier if she has onerecessive sex-linked gene. Barr body
- condensed X chromosome in somatic cells. Hemophilia - sex-linked disease. sex-linked = X-linked = males have 1 in 2 chance ofdisease.Evolution gene pool - total of all alleles in population Evolution - change in gene pool (not just phenotype)Ordering system for organisms:Kingdom > Phylum > Class > Order > Family> Genus > Species Ontogeny recapitulates phylogeny
= course
of development from embryo to organismreflects humans’ evolutionary history. e.g.,human fetus has pharyngeal pouches
Æ^ gilled
ancestor.3 new superkingdoms called “domains”1) Bacteria 2) Archaea 3) Eukarya
Species
- usually all organisms that can produce fertile offspring with each other. speciation - geographic isolation, habitat isolation, seasonal isolation, mechanicalisolation, gametic isolation, developmentalisolation, hybrid sterility, selective hybridelimination, and behavioral isolation. niche - way species exploits their environment survival of the fittest - one species will
exploit environs more efficiently – leading toextinction of other with same niche.2 operating reproductive strategies r-selection
: large numbers of offspring with no parental care K-selection
: slow maturing offspring, strong parental care
Æ^ sigmoidal growth curve leveling off at carrying capacity. Adaptive radiation
from single ancestral species. evolutionary bottleneck
: shift in allelic
frequencies of survivors of a crisis.Divergent evolution – 2 or more speciesevolving from same group from commonancestor.Convergent evolution – 2 speciesindependently evolving similar structures
Æ
homoplastic structures. eg, wings of bats andbirds. no common ancestor, but commonstructure.Some phenotypes vary gradually w/in species,such as height. Those that are distinct (yellowor white petals) is called polymorphism.Symbiosis – rel’ship b/w two species. ifbeneficial for both
Æ^ mutualism
beneficial for only one but neutral for other
Æ
commensalism
Benneficial for one, detrimental for other
Æ
parasitism
Hardy-Weinberg EquilibriumThere should be no change in gene pool ofsexually reproducing population posessing 5following conditions:1) large population2) mutational equilibrium3) immigration or emigration does not change
gene pool
random mating
no selection for fittest organism.No population has all 5 characteristics. Smallpopulations subject to genetic drift
Æ^ one
allele permanently lost due to death of all thecarriers.Binomial theorem: p² + 2pq + q² predicts genotypic frequency w/ only 2 allelesin populationso if A is dominant and a is recessive, and theyare only alleles for specific gene.if 80% of genes are A, 20% a.Same percentages for gametes.Probability that two A’s come together is0.8 squared = 0.
Two s’s come together0.2 squared = 0.04 = 4%All remaining = heterozygotes
only 2 alleles, so p + q =1.Origin of Lifeuniverse is 12-15 B yrs oldearly earth probably had atmosphere mainlyfrom N2 and H2 gas, very little O2. Urey-Miller experiments of early earth: autosynthesis of molecules such as urea,amino acids, and adenine from just H2S, NH3,and CH4 methane.first cells thought to have been coacervates, orlipid protein layer bubbles. spontaneouslyform from fat.earliest organisms 3.6 Billion years old.2.3 B yrs ago
Æ^ cyanobacteria. first able to use sunlight and water to reduce CO2 (fixateit). First photosynthetic bacteria.
Æ
atmosphere fills with O2. Eukaryotes come inat about 1.5 B yrs ago. millions of yrs later
Æ
multicellular organisms. Chordata
: phylum that contains humans. means “bilateral symetry” Deuterosomes –anus develops from or near blastopore. vs.proteosomes, where mouth develops from ornear the blasteopore. Chordates have coelom
(body cavity w/in mesoderm). Posessnotochord during development (embryonicaxial support), pharyngeal slits, dorsal, hollownerve cord, and tail. Vertebrata
- subphylum. have notochord replaced by segmented cartilage or bonestructure. brain enclosed in skull. Mammalsarose from reptiles about 220 million yearsago.
l^ = n-1 s subshells
look like sphers p subshells
look like peanuts rd 3 :^ magnetic
quantum
number:
m l-
designates precise orbital of subshell.
each
subshell has possible m
values from –l
l^ to +
l.
so for first shell n=1,
l = 0, only possible m
isl
0.For n = 3, 5 possible orbitals with m
equalingl
-2, -1, 0, +1, +2. th^4 number is e- spin number: m
. can be s
+½or + ½. Pauli exclusion principle – no 2 e’scan have same 4 coordinates.Heisenberg Uncertainty Principle dual nature of matter
inherent uncertainty in product of a particle’sposition and its momentum. on the order ofPlanck’s constant (6.63e-34 J-s).Energy Level of Electrons Aufbau principle
for new element, new e-tron added, as well.Nature prefers lower E state. more stability.electrons thus look for orbital with lowest estate whenever they add to atom. lowestsubshell. Electron configuration – lowest to highestenergy subshells1s2s2p3s3p3d4s4p4d4f5s5p5d5fif we follow arrows, they show us order ofincreasing energy for subshells. notnecessarily in numerical order: eg, 4s subshelllower energy level than 3d. 1s Æ 2s, 2p
Æ^ 3s, 3p
Æ^ 4s
Æ^ 3d
Æ^ 4p
Æ
5s… Think of “d” as dilatory in the order.*total number of e’s in your configurationshould equal that for atom / ion.Like charges repel. if placed close to eachother,
↑^ PE. explains why only 2 electrons can fit into one orbital.
explains
Hund’s rule
: e’s will not fill any
orbital in same subshell until all orbitals insubshell contain @ least 1 electron. unpairedelectrons will have parallel spins. (bus tocamden)This is moderated by having to climb an extraenergy step.
2p___ 2s____1s__Before 2p will start filling, 1s and 2s must bepaired. Planck’s quantum theory
: electromagnetic E
is quantized in discrete units. ΔE = hf (where h =Planck’s constant = 6.6e-34 J-s). Einstein
: if we think of light as particle (ie, photons), we can use same equation. deBroglie
: wave nature of electrons follow equation λ^ = h / mv when electron falls from higher E rung tolower E rung, energy given off in form ofphoton.photon must have frequency whichcorresponds to energy change
ΔE = hf
The reverse is true: photon collides w/electron, it can only bump electron to anotherrung. photoelectric effect
electron collision. proved light is made ofparticles (einstein). KE ectrons increases onlywhen intensity is increased by frequency ofphotons. minimum E required to eject anelectron called work function,
Φ, of metal.
KE of ejected electron given by E of photonminus work function KE = hf -
--------------------------------------------------------Gases Kinetics and Chemical Equilibrium gas^ – loose collection of weakly attractedatoms moving randomly. STP^ - 0°C and 1atm speed
- 481 m/s at STP mean free path
- distance traveled by gas between collisions ~ 1600Angstromsunlike liquids, all gases are miscible w/ eachother, regardless of polarity. with time andlow temp, heavier gases settle below lighteronesIdeal gas obeys ideal gas law: PV = nRT
where P is in atm, V in litres, T in Kelvin, andR is^ universal gas constant
(0.082 L-atm /
mol K) ideal gas: 1) zero volume; 2) no forces other thanrepellant 3) completely elastic 4) avg KE
α^ T
@ STP 1 mole of any gas occupies 22.4 Lpartial pressure = total pressure of mixturetimes mole fraction of gas
Æ
P= Xa^
Pa total where Xa = moles a / total moles of gas Dalton’s Law
- total gas pressure is sum of partial pressures of each gas. P= Ptotal^
+ P 1 2
+ P^ …. 3
KEavg = 3/2 RT
valid for both gases and liquids in sample of gas, KE of molecules will varyfrom molecule to molecule, but there will beaverage of the KE of the molecules that isproportional to the T and independent of thetype of gas.Graham’s law; v
/v^ =^1
√m/^2 √m^1
Effusion
: spreading of gas from high P to low P through a “pinhole.”effusion rate
/ effusion rate 1
=^ √m 2
/^ √m 2 1
Diffusion
- spreading of one gas into another gas or into empty space. approximated byGraham’s law.Real Gasesdeviate from ideal behavior when moleculesare close together. volume of moleculesbecome significant compared to volumearound molecules. High pressure / tinycontainer, low temp. Basically
, real gases take into account their own volume, so Vreal > Videal. nd^2 , real gases exhibit forces on each other. so P^ real
< P^ ideal Chemical Kineticsstudy of rxn mechanisms, rates.typically deals w/ reaction as it moves towardsequilibrium (eg, how fast it’s achieved). collision model
- reactants must collide. activation E
- threshold Arrhenius eqn: k = zpe
-Ea/RT
where z = collision frequency.rate of rxn increases with T.Equations for Rxn Ratesrates given in molarity per second (mol/L-s)
aA + bB
Æ^ cC + dD rate =
-1^ Δ[A] = -
Δ[B] = 1
Δ[C] = 1
Δ[D]
a^ t^
b^
c^
d
Intermediates
- products of one step, reactants in another. Often at very lowconcentration.rate law for fwd rxn rate^ forward
= k[A] f^
αβ[B]
where alpha and beta are the order of eachrespective reactant, the sum of them are theoverall order.Determining the Rate Law by Experimentrelatively simple.consider 2A + B + C
Æ^ 2D
compare a pair of trials at a timeif concentration doubles and rate doubles, thensuperscript is 1. if rate quadruples withdoubled concentration, exponent of 2. if ratedoes not change with doubling of aconcentration, that exponent is zero.add the exponents
Æ^ eg, third order.
Reversible Rxnsslow step = rate determining step. steps priorto it can still contribute to rate law.use equilibrium concentration of anyintermediates.Catalysis catalyst
- substance that increases rate of rxn w/o being consumed or permanently alteredlower the Ea. creates new rxn pathway whichincludes an intermediate-heterogeneous – in diff phase than reactantsand products-homogeneous – same phasefirst order uncatalyzed rxn example:rate = k
[A] 0
new one would be (if cat by acid):rate = k
[A] + K 0
[H+][A]H+^
catalyst changes Ea, but not delta G.Effects of Solvent on Rateliquids have 100x more collisions than gas.most with solvent
Æ^ no rxn.
solvation affects k. they can electricallyinsulate reactants, reducing forces b/w them.Equilibrium chemical equilibrium
= fwd rxn rate equals
reverse. no change in [pdts] or [rcts]
consider A
ÆB
forward rate law is rate = kf[A]reverse is rate =kr[B].they are directly proportional to each other.@ equilibrium [B] > [A], kf > krrate definition rate = -
Δ[A]a t rate at equilibrium is zero. does not mean rxnrate is zero. K = [C]
c^ d^ [D]^
= Products
coefficients
a^ [A] [B] b^ = Reactants
coefficients
equilibrium constant depends only on Tdon’t confuse with equilibrium itself.K has no units. proportion
Æ^ activity.
good for all equations, including non-elementary*Do not include solids or pure liquids (egwater)Partial Pressure Equilibrium Constantrxns for more than 1 pathway. any 2 or moresingle rxns or series resulting in same productsfrom same reactants must have same Keq.Kp is partial pressure Keq, n sum ofcoefficients of products minus sum of coeff ofreactants.Reaction QuotientFor reactions not at equilibrium… Q =^ Products
coefficients Reactants
coefficients use to predict direction of rxn.we always move toward equilibrium. Q
ÆK
if Q = K
Æ^ equilibrium
; if Q>K,
products>reactants than
when at equilibrium
rxn rate reverse > fwd
left shift
if Q < K
Æ^ products < reactants than
when at
equilibrium
. rxn rate fwd > reverse.
right
shift. Le Chatelier’s Principlewhen a system at equilibrium is stressed,system will shift to reduce stress. 3 stressors 1) addition or removal of pdt or rct2) changing P of system3) heating or cooling systemconsider the following:N(g) + 3H^2
(g)^ Æ 2
2NH^3
(g) + Heat
if we add N2 gas to rigid container, rxn movesright. H2 partial pressure also reduced bc it’sforward rxn. NH3 and heat created.if we raise T, rxn pushed to left. NH3decreased.if size of container reduced in constant temp,or when solution is concentrated/diluted, rxnmoves to side of least gas moles. Does not always predict correct shift.exceptions include salts, solvation rxns, andnonreactive gas. Helium does not affectequilibrium at all. Thermodynamicsstudy of energy and macroscopic properties.divide universe into system and surroundings. System
ΔE?^
ΔM?
Open
Yes^
Yes
Closed
Yes^
No
Isolated
No^
No
State functions
- physical condition of system. pathway independent. extensive - change w/ amount in system. eg, volume, number of moles. intensive - independent of system’s size. Pressure and temperature, eg.Heataka, “q.” movement of E via Always from hotto cold (down the gradient).1)^ conduction - mollecular collisions. requires physical contact. substances conduct atdifferent conductivity,
k.
2)^ convection
- heat txfer via fluid movements, such as air currents.3)^ radiation . via e-magnetic waves. all objects at T > 0K radiate some heat, some e-magnetic waves. only type that txfers throughvacuum.Workany energy transfer that isn’t heat. PV work - a system at rest with no gravitational PE or KE, but pressure andvolume change create work. w = P
ΔV (constant pressure) th^0 Law
- temperature exists rd^3 law - perfect crystal at 0 K is assigned entropy value of zero. all other substances andall T’s have positive entropy value. First Law
of Thermodynamics
E of system and surroundings alwaysconserved. ΔE = q + w (where work on system considered positive)Heat Enginesgas pushes against piston, now held by outsideforce we can control. heat gas, it expandswhile at constant T. Total E of gas does notchange as it expands. energy of heat we’veadded changes completely into PV work doneby force against piston. heat of liquid getsdisipated into a cold reservoir nearby.compressed to original state, back to where westarted. nd^2 law of Thermodynamics
changed completely into work in a cyclicalprocess.reverse of heat engine = refridgerator. Thermodynamic State Functions
: Internal
Energy (U); Temperature (T); Pressure (P);Volume (V); Enthalpy (H); Entropy (S); GibbsEnergy (G).Internal Energymolecular energy such as vibrational,rotational, translational, etc. ΔU = q + w Temperaturehow fast molecules are moving / vibrating. Æ^ hot T bc of more molecular movement.Described by zeroth law.avg KE of single molecule in a fluid: KEavg = 3/2 kT Kelvin = Celsius + 273virtually all phys properties change w/ TPressureP of ideal gas is random translational KE pervolume.PV = nRTEnthalpyextra capacity to do PV work. cannot beintuited, just memorize equation: ΔH =
ΔU + P
ΔV
Standard State
(not same as STP).
reference form for a substance at any chosentemperature T and P of 750 torr.Standard Enthalpy of Formation –
ΔH°f
Δ^ in
E enthalpy for rxn that creates 1 mole of cpdfrom raw elements. the naught symbol
indicates standard state conditions. considerwater:H2(g) + fiO2(g)
Æ^ H20(l) ΔH°f = -285.8kj/molFor rxns involving no change in P,
ΔH°f = q
Hess’s Law
: When you add rxns, you add their enthalpies. ΔH°f reaction =
ΔH°f products -
ΔH°f rcts
endothermic = positive enthalpyexothermic = negative enthalpytop of the hill in a rxn graph = transition state catalyst
lowers Ea of fwd and rev. rxns affects the rate, NOT the equilibrium, andNOT the enthalpy.Entropynature’s tendency towards disorder (S)more likely
α^ more entropy nd^2 law of thermodynamics
isolated system never decreases. ΔS(sys) +
ΔS (surr) =
ΔS (univ) > 0
fwd entropy = (-) reverse entropy“reversible” = Ea lower than fwd Ea.irreversible = “” Opposite Entropy
, not energy, dictates direction of rxn. it increases rd^3 Law of Thermodynamics
for any pure substance @ absolute zero and ininternal equilibrium.entropy units are J/K.Gibbs Free Energyequilibrium achieved by maximizing entropyof universe. ΔG =
ΔH – T
ΔS
a negative
ΔG usually implies spontanaeity it is a state function. non-PV work. eg,contracting muscles, transmitting nerves,batteries.deals with change of enthalpy / entropy of asystem.If + enthalpy, -entropy
Æ^ nonspontaneous
If – enthalpy, +entropy
Æ^ spontaneous
higher T favors direction favored by entropy
Solutions solution
: homogenous mixture of 2+ cpds in single phase, eg, solid, liquid, gas. solvent
: compound which there is more of. solute
: cpd of which there is less. Colloidslike soln, but only solute particles are larger.eg, hemoglobin. usually can’t passsemipermeable membrane.More Solutions dissolved
- when solute is mixed w/ solvent like dissolves like
dissolve nonpolar solutes, etc. London dispersion forces
nonpolar molecules. weak interactions. Ionic cpds
- dissolved by polar solvents. break into cations and anions surrounded byrespectively charged ends of polar solvent.called
solvation
. Water does this really well. H+ sides of H20 would surround Cl- ion,whereas O- side would surround Na+ ion.water-solvated =
hydration.
said to be in
aqueous phase.water is poor conductor of electricity unless itcontains
electrolytes
, cpds that form ions in aq
soln.Be aware of some common ions: nitrite
- NO 2
,^ Nitrate
- NO , 3
sulfite
2- SO 3
sulfate
2- SO 4
,^ hypochlorite
- ClO , cholrate - ClO 3 ,^ perchlorate
ClO^4
2- CO 3
bicarbonate
HCO
3- PO 4
Units of Concentration Molarity (M)
= moles solute / volume solution Molality (
m)^ = moles solute / kg solvent Mole fraction (
X )^ = mols solute / all mols mass %
= mass solute / total mass soln x 100 ppm^ =^ mass solute / total mass soln x 10
6
“parts per million”Soln concentrations always given in terms ofthe form of the solute before dissolutioneg, 1 mol NaCL + 1 L H20 = approximately 1molar solution NOT 2 molar, even thoughNaCl goes to 2 ions.Normality measures number of protons peracid. H
SO 2 4
would be 2 normal, whereas HCl would be 1 normal.Solution FormationPhysical rxn:3 steps: 1) breaking of solute molecules, 2)breaking of solvent molecules, 3) formingintermolecular bonds b/w solvent and solute.E required to break bond.
heat of soln given by ΔHsol =
ΔH1 +
ΔH2 +
ΔH
first 2 steps endothermic, last is exothermic breaking a bond always requires energyinput. solution with –
ΔH will give off heat
when it forms. Solution that gives off heatwhen forming creates stronger bonds w/insolution. positive heat of solution
Æ^ weaker
intermolecular bonds than before forming of solutions
α^ entropy
(solutions usually more disordered than itsseparated pure substances)Vapor PressureEquilibrium b/w liquid and gas phases of cpdwhen it moves quickly… VP necessary tobring liquid and gas phases to equilibrium isvapor pressure of the cpd.Clausius-Clapeyron as it relates to VP: ln(Pv) = -
ΔHvap (1) + CR^
(T)
vaporization is ENDOthermicso^ Æ^
↑VP^ α
↑T
when VP = local atmosph pressure
Æ^ boil
melting is T at which vpliquid = vpsolid nonvolatile solute
pressure. Raoult’s Law (nonvolatile)
soln is solvent, then the vapor pressure will be97% of the vapor pressure of the pure solvent.^ P
= Xv a P a Raoult’s Law (volatile)
solven, vapor pressure will be 97% of thevapor pressure of the pure solven PLUS 3% ofthe vp of the pure solute.^ P
= Xv a PX a +^
Pbb
Negative heats of soln form stronger bondsand lower vp; Positive heats of soln formweaker bonds and raise vp.Solubilitysolute’s tendency to dissolve in solvent.on MCAT: usually salt in water.reverse rxn:
precipitation
when rate of dissolution = precipitation Æ^ saturated. Equilibrium of solvation rxn: own eq constant, solubility product Ksp.set equal to products over reactants raised totheir coefficients in balanced equation. leaveout pure solids, liquids.
elemental atoms
Flourine
Hydrogen
bonded to metal
Oxygen
Compounds: Group 1 elements
Group 2
Group 5
Group 6
Group 7
(first table has priority over 2
nd^ )
reducing agent / reductant:
cpd whose
element gives e-trons to atom oxidizing agent / oxidant:
compound
containing the atom that is being reduced.Potentialselectric potential E associated w/ any rxn.when you reverse the rxn, it’s E’s signswitchespositive E voltage
Æ^ spontaneous rxn
negative E voltage
Æ^ endergonic
Nickel, Iron, Zinc, and water do notspontaneously oxidize, or give up theirelectrons.half reaction potential is NOT multiplied whenrxn is multiplied, but half reactions areADDITIVE.Galvanic/Voltaic Cellturns chemical energy into electrical energy. salt bridge
- electrolyte conduction solution TEIET
- Terminals, electrodes, ionic conductor, electrodes, terminal.
emf^ is the
voltage b/w T and T.electrodes anode
- negative sign. oxidation happens here. cathode
- positive sign. reduction happens here.“RED CAT” mneumonicboth usually a strip of metal in solution.one side may be called a “half cell.” cell potential E / electromotive force (emf):^ potential difference between terminals whennot connected. connection
Æ^ reduces voltage
due to internal resistance in the cell.electrons flow alphabeticallyfrom^ a node to
c athode.
bc electrons are negatively charged, like repelslike.cell potential for galvanic cell always +Free Energy and Chemical Energy ΔG = -nFE
max determines a spontaneous rxnF is faraday’s constant (~100,000 C / mol)w=qV ΔG° = -RTln(Keq) where K equals eq constantQ is where rxn does not yet equal equilibrium if K = 1
then
ΔG° = 0
if K > 1
then
ΔG° < 0
if K < 1
then
ΔG° > 0
that is to say, if rxn has Keq that’s greater than1, it will be spontaneous at STP.Nernst equation:E = E° - 0.06 log (Q)
n Concentration Cella cell that is taking place in two jars. never atstandard conditions.never @ standard conditions, so use nernst. galvanic
cells have + cell potential electrolytic
cells have (-) cell potential Red Cat, An Ox
Physics
Key to solving probs: well drawn diagram.write a know/want table.vectors and scalars vector
has magnitude and direction scalar
has magnitude only to add vectors, place head of first vector to tailof second vector, draw arrow from tail of firstto head of second.multiplyingvectors can be multiplied/divided by scalarseg, mass (scalar) times accel (vector)
Æ^ force (a vector)
any vector can be broken up into componentvectors, whose sum is the original. lengths of components
and O=Hsin
A=Hcos
these values w/ be providedcommon MCAT triangles: 3/4/5; and 5/12/13speed = distance/t ; velocity = displacement/ta =^ Δv / t velocity and accel not always in samedirectionUniformly Accelerated Motionconstant a. x= x^0
+ v^ t +1/2 at^0
2
v = v^ o
+ at (^2) v = v 2 + 2axo v^ = (v + vavg^
)o^2 Displacement versus Time Graphdisplacement versus time.upward slope: + velocitydownward:
0 accel curve:
+/- accel slope = velocity Velocity versus Time Graph slope = acceleration Projectile Motionseparate the projectile path into perpendicularcomponents. peak height of projectile given by: v^ sinΦo^
=^ √(2gh)
when v. is zero. acceleration on the ball is constant (-9.8m/s)in the absence of air resistance, mass does notaffect projectile motion.Air resisancesurface area
α^ air resistance irregular, rough objects
α^ “ “
higher velocity
α^ “ “ Mass^
α^ 1/air resistance, bc less affected by it.(think of an anvil versus hollow rubber ball)Force inertia
- tendency to remain in present state Mass
- quantitative measure of inertia (kg) Weight
- gravitational force on an earth (N)on earth this is “mg”
Center of Mass –
single point at which all
mass is concentrated. any force here in anydirection, same magnitude of acceleration…sometimes CoM is not “in” the object (a ring) center of gravity
- single point where force of
gravity can be applied to entire mass.For MCAT assume CoM = CoGforces on MCAT:1)^ gravitational force
(mg);
2)^ electromagnetic force
(charged object or
magnet)3)^ contact force
- perpendicular to surface (aka normal force) and/or parallel to surface(friction)
mgcos
F(T)
fk mgsin
mgcos
mg
Newton’s 1
st^ Law:
law of inertia.
Newton’s 2
nd^ Law:
F = ma
Newton’s 3
rd^ Law
: every force has opposite
forceNewton’s Law of Universal Gravitation: F=Gm
m (^1 22) r G = 6.67 e-11 m
3 /kg-s F of A on B equals F of B on Awhy earth doesn’t move when we jump on it?too massive
F^
=^
tiny a
huuuuuuuge massinclined planewithout friction, only forces are Fn and gravitymgsin
Φ^ Φ
Shortcut to inclined planes: Normal force = mgcos
one portion counters some gravitythe rest is accel.gravitational = mgsin
Circular Motion / Centripetal Force^2 a^ =v^ /rc^
v
F^ =mvc^
(^2) r
F^ c r
Friction1) Normal force always perpendicular tocontact surface2) F^ always parallel to contact surfacer^ static friction
- force oppositng motion when contiguous surfaces are not moving rel. to eachother. Kinetic friction - force resisting motion once the two surfaces start sliding.for any two surfaces, there are 2 coefficients offriction: u
and us^
.k f≤^ us^
Fsn f^ = uk^
F^ kn with tension problems, a box being held by astring, if no movement, F(T) = mgHooke’s Lawforce due to stretched or compressed object F = -k
Δx Equilibrium, Torque, and Energy equilibrium
: no translational / angular acceleration static equilib
: all velocities = 0 dynamic equilib
: nonzero but constant v
Fupward
= F
downward Frightward
= F leftward Only system not in equilib MCAT tests is onethat experiences translational acceleration.to solve these probs:1) write equations as though it were inequlibrium2) before solving, add “ma” to side w/ lessforce ΣF = ma Torquetwisting force. clockwise or counterclockwise.product of Force and position vector “r” τ^ = F x l
(assuming perpendicular force)
r = point of rotation.Solving torque probs: Fupward
= F
downward Frightward
= F leftward τclockwise
=^ τ counterclockwise
T
mg^
mg
In this example, mg1 and mg2 are clockwiseand equal in sum to force of tension T. Forces upwards = Forces downwardsalso, the torques are equal so Tx = mgd + mgLEnergyunits of joule (J). for macroscopic systemsunits of electron-volt (eV) for microscopic.one joule = 1 kg-m
2 2 /s^
KE = ½ mv
2 Potential Energy (U) U= mghg^ Elastic Potential Energy U^ = ½ ke^
(^2) Δx SystemsLaw of Conservation of energy: constant E E^ before
= E^ after WorkWork – transfer of energy via force, measuredin Joules. W = Fdcos
Φ^ for all forces except friction W =^ Δ
K +^ Δ
U
assuming no dissipation in form of heatConservative / Nonconservative ForcesLaw of Cons. of Mechanical E| ΔK| = |
ΔU|
Nonconservative forces – those that changemechanical E when they do work. KEfrictional force and the pushing and pulling ofanimals.for this: W =
ΔK +
ΔU
Work and Friction
ΔK +
ΔU = fdcos
if internal energy change is avail use formula
W =^ Δ
K +^ Δ
U +^ Δ
E^ i
Powerrate of energy transfer. unit is watt (W).equivalent to J/s. don’t confuse with W work.
P =^ Δ
Et
if you know force and time:
P =^ Wt^
Æ
P = Fvcos
Momentum, Machines, Radioactive DecayMomentum:
p = mv given in kg-m / smomentum is always conserved.momentum is a vector.Collisions Elastic
- mechanical E conserved. no E dissipated to heat, sound, etc. eg, atomiccollisions.
U+ Ki^
**= Ui f
Inelastic
- colliding objects lose some mech E to internal energy. Completely inelastic - when colliding objects
stick together upon collision.can use conserv. of momentum for inelastic:
p^ = pi^
f
can be further broken down into
p(x)= p(x)i^
f p(y)^ = p(y)i^
f
might have to use cos/sin to break into vectorsmomentum is conserved before and aftercollision…Reverse Collisionsopposite of completely elastic: one objectspontaneously combusts into 2.--- Impulse (J) is equal to change in momentum J =^ Δ p J = F
Δtavg Δmv = F
Δtavg Machinesif you see on MCAT, ideal machines reduceforce but don’t change work.
ramp: inclined plane. pushing an object upramp, you are pushing mgsin
W = mghW=Fd work is held constant, so F^ α^ 1/d lever^
- based on torque. like ramp, allows us to increase the distance over which force acts. pulleys
are actually modified levers. multiple tension strings add up to counter act mg. Radioactive Decay Particle
Symbol
alpha
(^4) α 2
beta^
0 e-^
positron
+β^ or
0 e+^
gamma
γ
Half-Life Problems 4 variables
: initial amnt of substance, final amount of substance, number of half lives, andthe half life. MCAT will give you 3 of these. electron capture : 201/80Hg +
0 e --> 201/79 Au-^ Mass Defect E = mc
2 where c = 3x
8 m/s Fission and Fusion Fusion
- combining of 2 nuclei to form heavier nucleus. Fission - splitting of single nucleus to 2 lighter. Fluids fluid^ - liquid or gas. conforms to shape of container. battleship floats bc ocean conformsto surface so that always normal force. density - “heaviness of fluid” units kg/m
3
ρ= m/V compression of a gas makes it more dense.assume not possible for solids, liquids.Specific Gravity- SG^ =^
ρsubstance
/^ ρ water know H20 density on MCAT: ρwater^
= 1000 kg/m
3 = 1g/cm
3
fluid pressure – result of molecular collisions. P = F/A
in units Pascal (Pa) sucking water out a straw, how’s it work? atmpressure above water in straw lower than atmpressure above water in cup.Fluids at rest – only perpendicular forces on it. P =^ ρ gy if an open container exposed to air:
P =^ ρ gy + P
atmosphere Patmosphere = 101kPa gauge pressure
- measure of pressure compared to local atmospheric Pabsolute P = pgauge + patm hydraulic lift - works via Pascal’s principle. Fd^ = F^1
d^ or 2 2
FA^1
= F 1 2
A 2
Fbuoyant
= mg =water^
ρVgfluid^
fraction submerged =
ρfloating object^ ρ
fluid
an object floating displaces its weight in fluid,a submerged object displaces its volume influid.Fb doesn’t change w/ depth. V = A
Δh Fb = pg A
Δh Fb = pg
Δh A ΔP = pg
Δh random translational motion
fluid P at rest uniform translational motion
equally by all the molecules at a location offluid. Ideal fluid
- no viscosity; 2) incompressible; 3) steady/laminar flow; 4) notrotating.^ Æ^ most likely to show up on MCATassume non-changing volume…water through a pipe has
volume =
(^2) πr xd
continuity equation: Q = Av where Q = flow rate I = pQ = pAv where I equals mass flow rate.flow rates are constant in an ideal fluid. Bernouli’s Equation (memorize):P + pgh + 1/2 pv
2 = K
where K is fluid-specific constant.where h is distance above some arbitrary pointsum of the three terms is constant throughoutthe fluid. v =^ √(2gh) velocity of fluid as it leaves a spicket. Non-Ideal Fluid
- drag and viscocity act to
impede flow. the narrower the pipe, thegreater the drag. (greater velocity, too).slower than ideal fluid, but similar principles.
ΔP = QR Surface Tensionalthough denser than H20, a needle can floaton water. due to intensity of intermolecularforces per unit length. capillary action
- fluid may be pulled up a thin tube. intermolecular/cohesive forces andadhesive forces (sticking to each other andsticking to the tube.Solids Stress = F/A
in units N/m
2
Strain
=^ Δdimension / original dimension strain responds to stress. Modulus of elasticity = stress/strain 3 moduli to know for MCAT:1) Young’s modulus (E) [tensile]2) shear modulus
(G) [shear]
- bulk modulus
(B)[compression/expansion] E = (F/A)/(
Δ/h)o^ G = (F/A)/(
Δ/x^ )o^ B =^
ΔP/(Δ
V/V)o^ Waves wave
- txfer of momentum and E from one point to another. for MCAT, assume ideal. wavelength
λ^ – measured crest-to-crest frequency (f)
- number of wavelengths / timeunits of herts (Hz) or cycles/s
aka s
v =^ λf period (T)
- reciprocal of frequency; T = 1/famplitude (A) - maximum displacement from zero.velocity is dictated by the wave’s medium.elasticity; inertia.for a gas, velocity increases with temperature.sound waves move more quickly thru hot gas... intensity (I) = ½ pw
2 2 Av
I =^ P^4 π
(^2) r Intensity levels and dB. if intensity
↑^ by a
factor of 10, the decibels increase by the“addition” of 10 decibels.eg, from 30 W/m
2 to 3000 W/m
2 = adding 20
decibels.^ β^ = 10log (I / Io) where Io is threshold intensity (lowest we canhear)
force is directed perpendicularly to bothvelocity and magnetic field.nd^2 right hand rule: point thumb in direction ofmoving positive charge (v), point fingers indirection of magnetic field (B) palm will pointdiagonally in direction of F. qvB = (mv
2 ) / r F = ilBsin
A changing magnetic field
Æ^ electric field.
changing magnetic flux
Æ^ emf E E = -^
ΔΦ Δt Faraday’s Law Overall picture:1) magnetic field is generated by movingcharge and;2) moving charge experiences force whenmoving through electric field. Æ^ F = qvB Light and optics electromagnetic wave
of electric and magnetic fields. transversewave.sppeed (c) at which wave propagates thru freespace is constant, equal to ratio of magnitudesof electric field and magnetic field: Light
- tiny sliver of em spectrum. visible light in wavelengths 390 to 700 nm
1nm = 1x
-9^ m
shorter wavelength
α^ violet light
Æ^ UV
longer wavelength
α^ red light
Æ^ infrared
each wavelength has corresponding frequencyspeed of light in vacuum is constant.from c = f
λ^ Æ^ c = f λ light slower when propagating thru medium.index of refraction..^ n = c / v when light crosses into new medium, f remainssame, but
λ^ changes
indeces on MCAT: water- 1.3glass- 1.5 plane-polarized light
fields oriented in same direction. light’s dual nature
but has E transformative properties like aparticle.angle of incidence measured from animaginary perpendicular line to the surface.
of incedence is between line normal and ray oflight.^
Φ^ reflection is between normal line and deflected light.
Φ^ refracted is the ray of light in new medium.angle of reflection (same medium): Φincidence =
Φreflection angle of refraction (new medium): n^ sinΦ^1
= n 1 sinΦ 2
2
Ephoton = hf higher frequencies, such as violet and bluelight, have more E than lower f’s.when light moves to higher n,
Φ^ can be so
great as to cause total internal reflection.
Æ
all photons reflected @ angle of reflection, norefraction. “critical” angle. Diffraction
- another type of wave-bending phenomenon. light thru small slit. size ofopening ~ wavelength or smaller. constructivevs destructive interference. smaller theopening
α^ larger the opening
α^ greater bending
of waveImagesmirrors reflect light; lenses refract light.our mind doesn’t account for light bendingin other mediums:Person
water
real fish
brain’s fish
An image may or may not exist: virtual image
- does not exist outside of mind of observer; no light rays emanate from virtualimage. no image would appear on paper. ourreflection in a mirror. brain’s fish above. real image - exists separately from obs. rays of light actually intersect and then emanate
from point of intersection. if sheet were there,image would appear on it.Mirrors and Lensesmirrors – convex and concavelenses
- converging, diverging. concave looks like a cave, reverting back tocavement would be a divergement.always assume light originates from object.thicker center convergesassume spherical mirrors for MCAT.light from horizontal rays reflected by concavemirrors to focus on a single point,
focal point
focal point
α^ radius of curvature. f^ mirror
= ½ r focal point is also affected by refractiveindices of lens and medium of lens. alsoaffected of radii of curvature of both sides.power of a lens. in units of diopters (m
-1^ ):
P= 1/flens^ Ray diagrams are not useful for MCAT.overview of ray diagrams: convex mirror
(object same side): image behind, upright, smaller, not real. concave mirror
: object same side, image behind is upright, larger, not real. Diverging lens
: object far side, image farside is upright, smaller, and virtual.. Converging lens:
object far side, image
farside, larger, upright, and virtual.lateral magnification m – ratio of size of imageto size of object. h1 vs. h0 m = -d
= h^ i^ i d h^ o^ o angular magnification: mΦ^ =
Φi^
Φ^ obj. to eye, front of lens Φnp^
Φ^ obj. to eye, at near point
for any mirror or lens, distance of imge relatedto focal length and distance of object: 1 = 1
+^
f^ d
o^
d^ i
hardest part is determiningwhen value is + or - In any double system, use first image as theobject of the 2
nd^. for a convex mirror or diverging lens, f isalways negative.for a concave mirror and converging lens, f isalways positive. P = 1 =
1 + 1f d^ i^
d^ o M =^
-d= hi^
i d^ o^
h^ o f^ mirrors
= ½ r Two lens systemson MCAT would be microscope or teloscope: M = m
m 1 2 P= Peff^
+ P 1 2
Notes from 6.24.08all nitrates & sodium salts are water solublesingle bond length > double > triplegiven: Pb(OH)
Í^ Î
Pb2+ and 2OH-
if pH raised, rxn would shift leftP = IV“proton” = H+ = ionPhoton E
Æ^ ejected electron E ionization energy reached. all extra energy isfor the electron to have after ejection.eg, if 12 eV required to eject, and photon is15eV, e- has 3eV of KE.KE electron
α^ Voltage Xray emmission
α^ Intensity W = Fd ↑^ KE^
α^ ↑^ evaporation d = ½ at
2 Translational equilibrium = all F’s cancel =acceleration is zero α^ particle decay = Helium ejection d^ object
=^
h^ object d^ image^
h^ image Cu(s) + H2SO
Æ^ SO2 + Cu+ sulfur’s oxi state went from +
Æ^ +
Power = work / timeShort period
α^ short wavelength Harmonic:
st^ 1
nd^2
rd 3
λ<^1
λ^2
λ^3
P<^1
P^2
P^3
f>^1
f^2
>^ f^3
guitar harmonics always sound highhigh pitch
α^ high frequency P^ α^ wavelength
α^ harmonic number
α^ 1/f
harmonic
- multiple of the original frequency. th^4 harmonic is 16x natural frequencyas determined by
n 2
λf = v = 3x
8 m/s = speed of light voltage sources in parallel produce sameoutput voltage as single source; but if in series,their voltages would be additive.
freezing pt depression is colligative:totally dependent on # of solute particles inwater ↑^ molarity of solute
α^ ↓^ Tm
½ equiv point (first flat part)
[Conj. base] are equal.“reducing agent”
Æ^ causes reduction. eg, Fe.
----------------------------------------------------BS all somatic cells in body have same DNA /Chromosomes regardless of stage of lifecholesterol – precursor to steroid horomones
Æ^ estrogen vasoconstriction of intestinal villi lacteals
Æ^ ↓^ fat absorption crossing Tt x Ttone would expect Mendelian ratio of 3::1 oftall to short plantsmetabolism of aa’s from proteins
Æ^ see
Nitrogen urine concentration
↑^ α^ starvation
starvation: carbs, lipids used up, start breakingdown body proteinsC=O bond makes molecule more polar
↑^ polarity
α^ BP
chips, air bubbles break surface tension ofliquid, preventing superheating during avacuum filtrationHeat distillation flask @ slower rate
Æ^ better
fractionationStereogenic carbon = chirality centerdiff makeup
Æ^ diff enantiomers chiral if 4 diff constituents
Æ^ dbl bonded carbons are not ableto be chiral. Boiling point: when vapor pressure of liquid =surface pressure ↓^ BP^ α^ surface of liquid
methyl ketone formation
Æ^ (+) iodoform test
acetone on the NMR – 6H’s the same
Æ
singlet.
If rare gene, assume only 1 parent has it, andthat it’s recessive.if P phosphorylates R thenP splits /uses ATP
Æ^ ADP, and R becomes phosphorylated: R-(p)now activated. to de-phosphorylate is to quickly deactivatedistal tubule – reabsorbs glucose. ↓^ Hb Hg
α^ ↓^ GFR rate
α^ ↑^ reabsorption
albumin
↑^ α^ hypertonic Hb
Æ^ flow of H20 from tissue to bloodstreamProtein such as pepsin operates well at pH of 2or 1.5, but if as low as pH 1, will be denaturedand no longer operate.PTH^ ↓^
α^ ↑^ Ca
2+ Calciton(in) – brings Ca
2+^ in-to bone
Parathy(rid) – Ca
2+^ gotten rid from bone.
edema caused by
↓^ albumin,
↑^ body tissue
swelling.KappacofigusKPCOFiGuS-------------
Æ^ relatedness (Br2 + CCl4)
Æ^ turns colorless if dbl bond formed. “dehydration”A^ Æ^
B
removing pdt A as it is formed will cause aleftward shiftImprinting – perception of object enhancedduring critical development period.Cyclohexane has lowest heat of combustionamong cyclo-anes bc highly stable chairconfiguration.Steric hindrance
Æ^ bad nucleophile Practice test notesreview circuits, plain mirrors, soln chemistry,e structure, sound, atomic, nuclear structure,skip VR nat sciences and double check them,immune / circulatory systems, digestiveenzymes.tend to have 10 min at end of each section.mark liberally. PS Φ^ of tilt most important in incline probs
van der walls, aka London dispersion^ α^ polarizability^ α^ boiling point^ α^ number of electrons32g O2 = 1 mol O2Doppler effect. As signal approaches,frequency gets higher. Δf = -vf^
c where c is speed of the mediumCsound < Cradio“apparent loss of mass” = mass of fluiddisplaced“common ion effect” – saturated soln, eg NaCl
if you add any other soln that hasNa+ or Cl-, you’re gonna getprecipitate Resonant wavelength of pipe or tubeopen pipe has resonant wavelength = 2xlmechanical waves such as water/sound Æ^ only Energy is propegatedelectrons have dual energy/matterphenomenonw/ fixed potential difference (voltage) betweencathode and anode, electric field
α^ 1/L
E = (V – IR) / L electron @ cathode has V = to voltage in eVincedent photons only affect # of electronsemitted, not their energies.electron accelerates from anode to cathode.^2 P = I^
R (amps)x(ohms)
Æ^ Watts
electron ejections
↑^ α^ current flow (I)
photon frequency
α^ speed of ejected e-
radiation emitted when e’s
↓^ orbital
currents in parallel resistors
α^ 1/indiv resistors
BSa-choline / morphine /heroin
Æ^ constricts
pupils. “pinpoint” pupils diagnostic of opiateintoxification.
nor/epinephrine
Æ^ fight or flight / sympa
response
Æ^ dilated pupils IR peak around 1700
Æ^ C=O double-bond.
fungal spores metabolically inactive, haploid.aldosterone
Æ^ Na+ reabsorption
Æ^ H
reabsorptionimpurities in any substance
α^ melting (aka
freezing) point depression
α^ decreased
intermolecular interactions. why? interruptsintermolecular attraction. ↑^ intermolecular strength
α^ ↑^ boiling point
eg, why when you add salt to a pot of water itboils at a hotter temperature. because salt isattracted to water.amines soluble in dilute acid (eg, dilute HCl).carboxylic acids soluble in dilute base.ester^
Æhydrolysis
Æ^ ROH + ROOH
DNA replicates in S phase. saponification
: ester + (NaOH)
Æ^ Salt +
(acid)
Æ^ ROOH
molecular weight of cpds of varying structuresshould give a hint about the identity.lung inflation – possible because of negativepressure by suction.antibiotic resistance can be innate bc of chancemutations, eg, E Coli not killed with a firstround of antibiotics for infection.E Coli live in colon, move b/w colon andappendix freely. outside of them areabdominal cavity.Bacterial conjugation = recombination.Interneuron synapses
Æ^ pain, efferent neurons
to brain. Here are ealso the dorsal rootganglion attached to sensory neuron, feedsinterneuron, interneuron tells the motor neuronand effector to pull finger away from stove.Bacteria versus viruses: bacteria can reproducevia fission. √recessive people in populaetion = # ofrecessive genes in all. the remainder are the #of dominant genes in all.
Hardy-weinberg
says # of heterozygotes is equal to2 x (% of dominant genes alleles)
x (% of recessive alleles) aka 2pq.
Blood pressure: depends on 2 things:1) Cardiac output = stroke volume x heart rate2) resistance to blood flowanti-inflammatory drugs on a pt w/ septicshock: risk^ Æ
decrease of endogenous antibacterial
defense
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