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BIOL || 331 || Midterm || Review || Questions ||
with|| Precise || detailed || solutions
Glycogen || - || Correct || answer || ✔Polysaccharide; || branched; || animals Starch || - || Correct || answer || ✔Polysaccharide; || helical; || plants Overton || (1890s) || - || Correct || answer || ✔Cell || membrane || composed || of || lipids Red || blood || cells || - || Correct || answer || ✔Lack || internal || structures; || 7micrometers || in || diameter Gorter || and || Grendel || (1925) || - || Correct || answer || ✔Lipid || bilayer || (30 || angstroms) Singer || and || Nicholson || (1972) || - || Correct || answer || ✔Fluid || mosaic || model Glycerolipids || - || Correct || answer || ✔Eukaryotic; || glycerol || backbone || (-CHOH- CHOH-CHOH-) Glycerolipid || with || choline || head || - || Correct || answer || ✔Phosphatidylcholine || (lecithin)
Sphingolipids || - || Correct || answer || ✔Eukaryotic; || sphingosine || backbone || (-NH-) Sphingolipid || with || choline || head || - || Correct || answer || ✔Sphingomyelin Sterols || - || Correct || answer || ✔Eukaryotic; || 4 || member || ring, || less || amphipathic || than || other || membrane || lipids, || OH || head Three || major || classes || of || lipids || in || Eukaryotic || membranes || - || Correct || answer || ✔Glycerolipids, || Sphingolipids, || Sterols Phospholipids || - || Correct || answer || ✔Charge || and || identity || determined || by || head || group || (PA || -ve, || PC, || PE, || PS || -ve, || PI || -ve, || PG || -ve, || CL || -ve) Asymmetry || of || membrane || lipids || - || Correct || answer || ✔Exoplasmic: || SM || (sphingomyelin), || PC || (phosphatidylcholine) Cytosolic: || PS || (phosphatidylserine), || PE || (phosphatidylethanolamine) Cholesterol || is || roughly || even Eukaryotes || vs. || bacteria || vs. || archaebacteria || lipids || - || Correct || answer || ✔EUK: || Glycerolipids || (all || glycerol || 3-phosphate), || Sphingolipids, || Sterols Bacteria: || Glycerolipids || (glycerol || 3-phosphate, || no || PC || or || PI), || no || Sphingolipids || or || Sterols Archaebacteria: || Glycerolipids || (different || glycerol || 1-phosphate), || everything || else || present || but || very || different
Lipid-anchored || proteins || - || Correct || answer || ✔Insert || hydrophobic || group || into || internal || (cytoplasmic) || leaflet GPI-anchored || protein || inserts || into || external || leaflet; || protein || is || covalently || attached || by || glycosylation || to || PI Peripheral || proteins || - || Correct || answer || ✔Interact || with || phosphlipids || or || integral || proteins || on || either || side || of || the || membrane. || Removed || by || high || salt, || pH, || etc || without || disrupting || the || membrane Passive || transport || - || Correct || answer || ✔Diffusion || (hydrophobic || molecules), || Protein || pore || (ion || channels), || Transporter || mediated/facilitative || diffusion || (Uniporter || - || glucose || transporter) Primary || active || transport || pumps || - || Correct || answer || ✔1. || P-type || pump
- || F-type || and || V-type || proton || pumps
- || ABC || transporter P-type || pump || - || Correct || answer || ✔For || ions. || (eg. || Na+/K+ || ATPases, || Ca2+ || ATPase, || H+/K+ || ATPase, || H+ || pumps F-type || and || V-type || proton || pumps || - || Correct || answer || ✔1. || F-type: || to || produce || ATP || from || an || ion || gradient || - || run || backwards. || ATP || synthases
- || V-type: || in || vesicles || and || vacuoles. || To || pump || H+, || phosphate || from || ATP
ABC || transporter || - || Correct || answer || ✔For || moving || hydrophobic || (lipophilic) || compounds. || Can || function || as || flippases Na+ || and || K+ || concentrations || - || Correct || answer || ✔Na+: || extracellular || = || 150mM || Intracellular || = || 10mM K+: || extracellular || = || 5mM || Intracellular || = || 140mM Secondary || active || transport || - || Correct || answer || ✔Movement || driven || by || gradient || (created || from || ATP || hydrolysis || in || primary || active || transport)
- || Symporter: || move || one || molecule || against || its || concentration || gradient || and || another || down || its || electrochemical || gradient || (driving || ion)
- || Antiport: || opposite || directions The || asymmetric || distribution || of || charges || across || the || PM || produces || - || Correct || answer || ✔1. || A || chemical || (concentration) || gradient || (eg. || Na+ || for || cotransporters)
- || An || electrical || (voltage) || gradient || (eg. || Na+/K+ || ATPase || as || an || electrogenic || pump || - || 3Na+ || out, || 2K+ || in || = || -ve || cytosol) Together, || they || are || call || the || electrochemical || gradient Membrane || potential/voltage || gradient || - || Correct || answer || ✔Difference || in || electric || charge || across || the || PM Equilibrium || potential || of || Na || and || K || - || Correct || answer || ✔Na || Ek || = || +55mV K || Ek || = || -90mV
Action || potentials || - || Correct || answer || ✔Cause || Nerve || Impulses || Due || to || change || in || membrane || potential || of || electrically || excitable || cells || as || a || result || of || changes || in || Na || and || K || permeability Initiated || by || ligand-gated || ion || channels || and || propagated || by || voltage || gated || cation || channels Self || propagating || (unidirectional) Refractory || period || - || Correct || answer || ✔Inactivation || of || channels || to || ensure || propagation || is || in || one || direction Myelinated || neurons || - || Correct || answer || ✔increase || the || speed || of || electrical || impulse || propagation Nodes || of || Ranvier || - || Correct || answer || ✔Voltage || gated || Na+ || channel || are || located || in || gaps || (nodes) || in || the || Myelin || sheath Nodes || are || located || between || Schwann || cells Point || of || controversy || in || endosymbiotic || theory || - || Correct || answer || ✔Appearance || of || the || nuclear || envelope || from || PM || invagination mRNA || (Prok || vs || Euk) || - || Correct || answer || ✔Prok: || Ribosomal || binding || site || - || Shine || Dalgarno || sequence Euk: || Kozak || sequence || (-5 || to || -10bp), || 5' || cap || (m7 || guanine), || poly-A || tail, || 5'UTR || (has || loops || to || prevent || translation), ||
*poly || A || binding || protein || (PABP) || facilitates || translation Ribosomes || (Prok || vs || Euk) || - || Correct || answer || ✔Prok: || 70S || (30S || + || 50S) Euk: || 80S || (40S || + || 60S) || = || 24nm Subunits || assembled || in || the || nucleolus, || become || a || full || unit || with || mRNA || interaction || in || the || cytosol DAPI || - || Correct || answer || ✔Stains || DNA || blue Nucleolus || - || Correct || answer || ✔For || rRNA || synthesis/processing || and || ribosome || assembly 20micrometers Can || be || seen || in || non-dividing || cells || (not || in || mitosis) Amino || acyl || tRNA || synthetase || - || Correct || answer || ✔Adds || aa || to || 3' || end || of || tRNA || with || ATP 20 || types tRNA || - || Correct || answer || ✔ 31 || types || in || mammalian || cells, || 22 || in || mitochondria Wobble || at || 3rd || position Bacterial || translation || initiation || - || Correct || answer || ✔IF2: || Binds || to || GTP || (on/off || switch)
Initiation || of || protein || synthesis || - || Correct || answer || ✔Starts || on || free || ribosomes || in || the || cytoplasm || for || all || proteins SRP || - || Correct || answer || ✔Signal || recognition || particle Translation || stops || when || SRP || binds || to || exposed || signal || sequence Protein || synthesis || on || membrane-bound || ribosome || - || Correct || answer || ✔1. || SRP || recognizes || signal || sequence
- || SRP || binds || to || SRP || receptor || (causes || ribosome || to || bind || to || a || translocon || on || the || RER || membrane)
- || GTPase || activity || of || SRP/SRP || receptor || hydrolyzes || GTP
- || Translocon || binds || ribosome || using || the || energy || and || SRP || is || released
- || Translation || resumes. || Signal || sequence || inserts || into || and || binds || translocon. || Interaction || opens || the || channel || by || removing || the || plug Signal || peptidase || - || Correct || answer || ✔Cleaves || signal || sequence || once || peptide || is || in || the || RER || lumen Integral || membrane || protein || synthesis || on || membrane-bound || ribosome || and || positive || inside || rule || - || Correct || answer || ✔Integral || proteins || contain || hydrophobic || trans || membrane || segments || -> || will || be || retained || in || membrane Arrangement || within || the || membrane || is || determined || by || the || orientation || of || the || first || trans || membrane || segment Positive || inside || rule: || net || aa || charge || at || either || end || of || the || transmembrane || bias || the || direction || of || insertion || (+ve || end || (N || or || C) || will || face || ER || lumen)
N-linked || glycosylation || - || Correct || answer || ✔Targets || Asn-X-Ser/Thr || (recognized || by || oligosaccharyl || transferase) Oligosaccharide || tag || added || in || the || ER || lumen || (synthesized || on || both || sides || of || the || ER) Protein || quality || control || (ER) || - || Correct || answer || ✔Three || terminal || glucose || residues || for || quality || control || (from || glycosylation) Terminal || glucose || = || tag || for || chaperones || to || refold Polybiquitin Misfolded || proteins || destroyed || in || the || cytostol Calnexin BiP || + || membrane || sensor || proteins || - || Correct || answer || ✔Chaperones || that || recognize || misfolded || proteins || (Calnexin || for || glycoproteins) Pulse-chase || experiment || - || Correct || answer || ✔to || determine || where || proteins || move ER || - || Correct || answer || ✔Physically || connected || to || nuclear || envelope Contacts || all || organelles: || membrane || contact || sites || (MCS) RER || - || Correct || answer || ✔- || Synthesis || of || membrane || lipids
- || Synthesis || of || extracellular || proteins
- || Integral || membrane || protein || synthesis
Anterograde || vs. || retrograde || - || Correct || answer || ✔Anterograde || = || forward || transport Retrograde || = || backward || transport Clathrin || - || Correct || answer || ✔Triskelion: || 3 || heavy, || 3 || light || chains Makes || a || polyhedral || structure VTC || - || Correct || answer || ✔VTC: || vesicular || tubular || clusters Formed || when || COPII || vesicles || leaves || the || ER, || uncoat, || and || fuse || together Associate || with || motor || proteins || that || drag || them || along || microtubules || (uses || ATP) Retrograde || transport || purifies || secretory || cargo G-proteins Sar-1, || Sec-12/23/24/13/31 || - || Correct || answer || ✔ER || to || Golgi: || formation || of || COPII || vesicles
- || Sar-1-GDP || is || phosphorylated || (by || Sec12 || GEF). || Associates || with || the || membrane || as || Sar-1-GTP
- || COPII || coat || assembly: || Sar-1-GTP || recruits || proteins || (Sec || 23 || and || 24, || cargo || receptor). || Sec || 13 || and || Sec || 31 || interact || with || proteins || to || form || a || coat
- || Vesicle || detaches. || GTP || hydrolysis || for || uncoating SNARES || - || Correct || answer || ✔Required || for || fusion || of || vesicles
- || v-SNAREs || (vesicle) || for || budding
- || t-SNAREs || (target) || for || fusion v || and || t || associate || for || docking. || Tightly || associate || and || pull || to || fuse || vesicle. || ATPase || unfolds || SNARE || complex Rab-GTP || and || Rab || effector || (tether) || - || Correct || answer || ✔Give || specificity || to || fusion || reaction || of || vesicles Rab || effector || = || tethering || protein || to || restrict || vesicle || movement. || Attaches || to || Rab-GTP Phosphatidyl || inositols || (3 || types) || - || Correct || answer || ✔Molecular || switches || to || recruit || proteins || to || different || membrane || surfaces
- || PI(3)P || - || Endosomes
- || PI(4)P || - || Golgi
- || PI(4,5)P || - || Plasma || membrane
- || Kinases
- || Phosphatase || - || Correct || answer || ✔1. || Add || phosphate || from || ATP || to || target
- || Removes || phosphate 3 || Functions || of || the || secretory || pathway || - || Correct || answer || ✔1. || Secretion || of || proteins
- || Build || and || transport || integral || membrane || proteins
- || Facilitates || post-translational || modification
TGN || regulated || secretory || pathway || - || Correct || answer || ✔Stimuli || (eg. || insulin) || binds || to || receptor || to || cause || a || response || (eg. || relocalization || of || glucose || receptors || to || PM) LDL || - || Correct || answer || ✔LDL: || low || density || lipoprotein 22nm Contains || cholesterol || in || a || phosphlipid || monolayer Receptor || mediated || endocytosis || - || Correct || answer || ✔Extracellular || LDL || binds || to || LDL || receptor || in || clathrin || coated || pit || (on || the || PM), || into || a || clathrin || coated || vesicle || to || enther || the || cytosol, || uncoating, || fusion || with || endosome, || LDL || hydrolysed || and || free || cholesterol || is || released Receptor || is || returned || to || PM Endocytosis || is || eukaryotic "address" || of || proteins || - || Correct || answer || ✔Indicated || by || a || signal || sequence For || proteins || going || to || nuclei, || mitochondria, || plastids, || and || peroxisomes || --> || free || ribosome || synthesis || of || proteins Peroxisome || - || Correct || answer || ✔Membrane || is || a || bilayer Contains || oxidative || enzymes Oxidize || long || fatty || acids, || synthesize || plasmogens Forms || H2O2, || which || can || be || broken || down || by || catalase
Uptake || of || proteins || into || mitochondria || - || Correct || answer || ✔Requires || targeting || sequence: || presequence || and || unfolded || proteins || (due || to || chaperones || - || Hsp || 70), || voltage || dependent Internal || targeting || sequence || for || internal || membrane || protein PTS || - || Correct || answer || ✔Peroxisomal || Targeting || Signal: || mediates || uptake || of || proteins || into || the || peroxisome TOM || and || TIM || complexes || - || Correct || answer || ✔Uptake || of || proteins || into || mitochondria || for || protein || import
- || TOM: || Transporter || outer || membrane, || includes || a || receptor || and || channel
- || TIM: || Transporter || inner || membrane, || for || proteins || going || to || inner || mitochondrial || membrane/matrix. || TIM || 22 || = || to || the || inner || membrane, || TIM || 23 || = || to || the || matrix MPP || - || Correct || answer || ✔Mitochondrial || processing || peptidase: || cleaves || presequence Uptake || of || proteins || into || chloroplasts || - || Correct || answer || ✔Transit || peptide || sequence TIC || and || TOC Chaperones || unfold || proteins || (Hsp || 70) || in || the || cytosol || and || fold || in || the || chloroplasts || (Hsp || 60) TOC || and || TIC || - || Correct || answer || ✔Translocation || complexes || to || facilitate || import || on || proteins || to || chloroplasts || (channels): || outer || and || inner || membrane
Microtubule || growth || (polymerization) || - || Correct || answer || ✔Add || subunits || to || beta || (+) || end || - || fast || growing GTP || bound || beta || subunits || = || straight || protofilament, || hydrolysis || of || GTP || = || curved || (less || stable) Depolymerization || (peeling || of || microtubule) Reset || with || GDP-GTP || exchange Microtubule || dynamic || instability || - || Correct || answer || ✔GTP || dimers || hydrolyze || to || "zip" || microtubule || (assembly), || GTP || [cap] || is || hydrolyzed || --> || catastrophe, || tube || disassembly, || GTP || cap || regained || (rescue) || to || resume || growth If || GTP || was || not || hydrolyzed || (GTP-gamma), || tube || would || grow || continuously Kinesins || - || Correct || answer || ✔Motor || protein || (walks || on || MTs) *ATPase, || moves || toward || the || +end Member || of || kinesin-like || protein || (KLP) || family || *Moves || protein || toward || the || PM || (and || ER) 2 || heavy || and || 2 || light || chains || (tetramer) || and || globular || heads 16nm || steps, || 80nm || long Dynein || - || Correct || answer || ✔Motor || protein || (walks || on || MTs) *ATPase, || moves || toward || the || -end Large, || force-generating, || globular || heads Requires || a || dynactin || adaptor
Ciliary || dynein: || responsible || for || cilia/flagella || movement *Moves || toward || the || Golgi MTOCs || - || Correct || answer || ✔Microtubule || organizing || centers Control || number, || polarity, || and || assembly || time || and || location || of || microtulues/protofilaments Types || of || MTOCs || - || Correct || answer || ✔Centrosome || (interphase || cells), || spindle || pole || (mitosis), || basal || body || (cilia/flagella), || MTOC || (other) gamma-tubulin || - || Correct || answer || ✔essential || for || all || MTOCs || (assembly || of || MTs || forming || a || cap || at || the || minus || end) Stabilize || -end, || allowing || +end || to || grow gamma-TuRC || forms || a || -end || cap Centrosome || - || Correct || answer || ✔Responsible || for || nucleation || of || MTs || in || animal || cells Contains || 2 || centrioles || (perpendicuar) || surrounded || by || pericentriolar || material || (PCM) Centrosome || matrix || has || nucleating || sites || (gamma || tubulin || complexes) || where || MTs || grow || from || (+end || outward) Actin || - || Correct || answer || ✔Can || bind || ATP || (not || GTP) ~40kDa
