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Grade 12 biology exam review with
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Dehydration synthesis - correct answer ✔ A reaction at which two molecules combine to create a larger molecule taking out H2O. Hydrolysis - correct answer ✔ A reaction at which a compound reacts with water to produce other compounds. Redox - correct answer ✔ A chemical reaction where atoms gain or lose electrons (LEO the lion says GER) Neutralization reaction - correct answer ✔ Where an acid and a base reacts to form H2O. Lipids - correct answer ✔ Made out of carbon, hydrogen and oxygen. The role of the lipids is to insulate the organs and joints. The are made up of ester bonds. Protein - correct answer ✔ Made out of amino acids and bonds are peptide bonds, the protein form enzymes, cell surface markers and cell membrane are protein channels. Carbohydrates - correct answer ✔ Made up of hydrogen, carbon and oxygen, it is the main source of energy, and the bonds are glycosidic linkages.
[->types of carbs= Monosaccharide= one sugar, Disaccharide= 2 sugars, Polysaccharide= many sugars (3 or more).] Nucleic Acid - correct answer ✔ Organisms store hereditary and genetic information that determine structural and functional characteristic. Enzymes - correct answer ✔ Lower activation energy and are catalyst. Factors affecting the reactions are temperature, ph, and concentration. (Enzyme shape) = Non-competitive- Does not compete for an active site. = Competitive- Able to enter active site to block normal substrate for Glycolysis - correct answer ✔ Happens in cytoplasm. 2 ATP are used to make 2 ADP in investment phase, 2 NAD are used to make 2 NADH and in payoff phase 4 ATP are used to make ADP and 2 H2O's are taken out. Pyruvate Oxidation - correct answer ✔ This occurs in the mitochondrial matrix 2 pyruvate and a NAD forms 2 NADH ,2 CO2 and 2 acetyl coa Krebs - correct answer ✔ Happens in mitochondrial matrix. 3 NADPH is made, 2 CO2 is made, 1 FADH is made, and 1 ATP is made. Oxidative phosphorylation - correct answer ✔ Involves a series of redox reaction, O2 is used to oxidize electron carriers FADH and NADH to produce ATP.
RNA - correct answer ✔ Leaves the nucleus and is single stranded, T pairs with uracil (u). DNA replication 1 - correct answer ✔ DNA gyrase relaxes the bonds of the helix. DNA replication 2 - correct answer ✔ DNA helicase unzips the helix. DNA replication 3 - correct answer ✔ SIngle stranded binding protein binds to open DNA strands. DNA replication 4 - correct answer ✔ Primase creates RNA primers used to start strand synthesis. DNA replication 5 - correct answer ✔ DNA polymerase III Synthesizes new complementary strands. DNA replication 6 - correct answer ✔ RNA polymerase I turn DNA into RNA DNA replication 7 - correct answer ✔ DNA ligase joins remaining gaps. DNA replication 8 - correct answer ✔ Polymerase III and II check for and correct errors.
Replication fork - correct answer ✔ Little lines are lagging strands and long straight line is leading strand. Helicase - correct answer ✔ Breaks down the hydrogen bonds between complementary base pairs. Single stranded binding pairs - correct answer ✔ Join into the base pairs to prevent reforming. DNA gyrase - correct answer ✔ Relieves tension during the stage of replication. Primase - correct answer ✔ Attaching complementary RNA primers on the exposed template strand. Polymerase III - correct answer ✔ use primers to synthesize new DNA from 5, to
Polymerase I - correct answer ✔ Goes along the strand to remove RNA primer DNA ligase - correct answer ✔ Joins the resulting gaps in the phosphate sugar backbone. Transcriptional - correct answer ✔ Regulates rate of transcription by proteins called transcription factors. Post- transcriptional - correct answer ✔ Splicing of introns and joining of exons.
Repressed - correct answer ✔ Happens when lactose is absent, this prevents RNA polymerase from attaching to the control region. This is a form of negative regulation. Induced - correct answer ✔ When lactose is present which attaches itself to the repressor protein, this changes the lac proteins shape and no longer binds to the operon. Point mutation - correct answer ✔ Mutation at a specific base pair in the gnome. Silent Mutation - correct answer ✔ No effect on the operation of the cell. Substitution Mutation - correct answer ✔ One base pair is substituted for another, most common type of mutation. Missense Mutation - correct answer ✔ Change in base alter a codon leading to a different aa in the protein sequence. Frameshift Mutation - correct answer ✔ Change in the reading frame resulting in different aa Deletion - correct answer ✔ One or more nucleotides removed from sequence. PCR - correct answer ✔ Cheap and easy way to duplicate DNA in Vitro.
Gel Electrophoresis - correct answer ✔ Goes through a machine (gel) one side positive one side neg, DNA goes through negative. When turned on they will swim to positive. Smaller will go faster so will be further ahead. Receptors - correct answer ✔ Detects stimuli such as cold, pain, etc. Negative FeedBack - correct answer ✔ A reaction that reduces the stimulus reaction ei. Your body trying to cool you down when you have a fever. Positive Feedback - correct answer ✔ A reaction that increases the stimulus reaction ei. Contractions occur when women give birth. Stimulus - correct answer ✔ A detectable change externally or internally environment. Thermoregulation - correct answer ✔ The maintenance of body temperature that keeps it a rage for cells to properly function. Homeotherm - correct answer ✔ An animal that maintains a stable body temperature regardless of the surrounding temp. Poikilotherm - correct answer ✔ An animal who's body temp varies and often matches the temp of external environment. Endotherm - correct answer ✔ Invertebrates, fish, and reptiles allow temp to fluctuate with the external environment.
Kidney - correct answer ✔ Removes waste, balances blood ph and maintains water balan Renal artery - correct answer ✔ Where blood from the heart is passed down. The Ureter - correct answer ✔ The forced out waste is sent down to, to be sent to the bladder for storage. Renal Vein - correct answer ✔ Where clean blood is sent out back into the circulatory system. Bladder - correct answer ✔ Stores urine before it is evacuated from the body. (note) -200= urge to pee -400= larger to pee -600= loss of control. Nephrons - correct answer ✔ Where waste is forced and filtered out by the glomerulus, then after waste is caught by funnels called the bowman's capsule. -Waste travels to the proximal tubule then to the loop of henle. -up to the distilled tubule into the collection duct -then flows to the calyx to the pelvis passed down to the bladder. Filtration - correct answer ✔ Water and solutes are brought down to the bowman's capsule. Reabsorption - correct answer ✔ Water and solutes are brought from the nephrons go back into the blood.
Secretion - correct answer ✔ Larger waste is brought to the distilled tubule using active transport. Arch Reflex - correct answer ✔ Neural circuit through spinal cord which does not use brain coordination What are the 5 sensors - correct answer ✔ -Receptors -sensory neuron -Interneuron in spinal cord -Motor neuron -Effector Vertebrate nervous system - correct answer ✔ (CNS) Coordinate centre is coming in and out of the brain. PNS= Nerves that carry signals from the central nervous system to the organs. Dendrites - correct answer ✔ Receives info and carries it to the cell body Axons - correct answer ✔ Carries nerve impulses away from the cell body Myelin Sheath - correct answer ✔ Fatty protection that insulates the neuron. Schwann Cells - correct answer ✔ Special types of glial that produces myelin sheaths.
Parathyroid - correct answer ✔ In the neck, parathyroid hormone is secreted to regulate calcium level in blood and bone metabolism. Adrenal gland - correct answer ✔ Is located on top of the kidney's, secretion of cortisol and aldosterone occurs to help control blood pressure and heart rate. Pineal gland - correct answer ✔ In the centre of the that secretes melatonin to maintain sleep pattern and regulate reproductive hormones.
