Ku Biol 546 Final Exam Exam Questions With Correct Verified Answers | 100% Pass (A+ Certified

KU BIOL 546 FINAL EXAM EXAM QUESTIONS WITH CORRECT VERIFIED ANSWERS | 100% PASS (A+ CERTIFIED 1. 1. Enzyme activity can be enhanced by special molecules such as ________ A. competitive inhibitors. B. non-competitive inhibitors. C. irreversible inhibitors. D. cofactors. E. None of the above: D. cofactors. 2. 2. The process that produces the most ATP molecules per molecule of glucose in a cell is A. substrate-level phosphorylation. B. oxidative phosphorylation. C. anaerobic glycolysis. D. aerobic glycolysis. E. Krebs (citric acid) cycle.: B. oxidative phosphorylation. 3. 3. Osmosis refers to the movement of what substance across semi-membranes? A. Glucose B. Charged particles C. Lipid molecules D. Water E. Solutes: D. Water 4. 4. Placing human red blood cells in a hypotonic solution would cause them to ____ A. swell. B. shrink. C. stay the same volume.: A. swell. 5. 5. During anaerobic conditions in the mammalian cell ____ A. pyruvate is converted to lactate. B. More ATP is produced in the mitochondria than in the cytoplasm. C. CO2 is produced in glycolysis. D. Answers A and C are correct. E. All answers are correct.: A. pyruvate is converted to lactate. 6. 6. A negative feedback mechanism in physiology ____ A. produces more products. B. produces stronger results. C. turns itself on. D. leads to a snowball effect. E. turns itself off.: E. turns itself off. 7. 7. What is the general purpose of positive feedback mechanisms? A. To maintain a constant internal environment. B. To anticipate changes in the environment. C. To return a variable toward the set point. D. To bring about a rapid change in the body. E. To continue a response.: D. To bring about a rapid change in the body. 8. 8. Water can be transported across cell membranes by the following process(es): A. by a pump driven by ATP in the membrane. B. by water channels in the membrane. C. by solute-coupled transport. D. answers B and C. E. answers A and B.: D. answers B and C. 9. 9. The diffusion rate of chemical X across a cell membrane can be decreased by ____. A. increasing the membrane permeability of X. B. increasing the concentration gradient for X across the membrane. C. increasing the area of diffusion. D. increasing the thickness of the membrane. E. answers A and C.: D. increasing the thickness of the membrane. 10. 10. Which feature(s) is(are) part of secondary active transport? A. ATP is needed. B. A compound is transported down its concentration gradient. C. More than one compound is transported across the membrane. D. Answers A and C. E. Answer A, B, and C.: E. Answer A, B, and C. 11. 11. What is the neurological effect of a drug that prevents priming of vesicles in the presynaptic terminal of the neuromuscular synapse? A. It stops sending impulses to muscles (paralysis). B. It continues sending impulses to muscles (seizures). C. It starts glial cells to produce action potentials. D. None of the above.: A. It stops sending impulses to muscles (paralysis). 12. 12. All of the following are TRUE statements about the action potential EXCEPT: A. Opening of the voltage-gated Na-channels will move the membrane poten-tial towards the equilibrium potential of Na. B. Opening of voltage-gated K-channels will move the membrane potential towards the equilibrium potential of K. C. The Hodgkin cycle causes the fast change in membrane potential during the rising phase of the action potential. D. The falling phase of the AP is mainly due to the movement of K+ ions. E. Voltage-gated Na-channels stay open longer than voltage gated K-channels- : E. Voltage-gated Na-channels stay open longer than voltage-gated K-channels 13. 13. The safety factor of an action potential is ____. A. the amount of depolarization above what is needed to reach threshold potential. B. the amount of depolarization from zero membrane potential to the peak of the action potential. C. the change from the membrane hyperpolarization level to the resting mem-brane potential. D. the spread of the depolarization along an axon membrane. E. the protective function of the myelin sheet.: A. the amount of depolarization above what is needed to reach threshold potential. 14. 14. Graded potentials _____ A. are local changes in membrane potential that occur in varying degrees of magnitude. B. are local changes in membrane potential that occur only when the threshold potential has been exceeded. C. can be depolarizations or hyperpolarizations. D. Answers A and C are correct. E. Answers B and C are correct.: D. Answers A and C are correct. 15. 15. If a presynaptic neuron is stimulated with a depolarizing current, and the ion flow through the voltage-gated Na+ channels equals the ion flow through the voltage-gated K+ channels, then ____ A. the equilibrium potential has been reached. B. the threshold potential has been reached. C. the reversal potential has been reached. D. the safety factor has been reached. E. the length constant has been reached.: B. the threshold potential has been reached. 16. 16. The sodium/potassium exchange pump in nerve membranes ____ A. stops working at the equilibrium potential. B. moves 3 Na ions out of the cell for every 2 K ions into the cell. C. requires ADP. D. is absent at the axon hillock. E. Answers A and C.: B. moves 3 Na ions out of the cell for every 2 K ions into the cell. 17. 17. In nerve membranes that show a fast accommodation during a continued stimulation ____ A. the action potential amplitude will increase slowly over time. B. the production of threshold potentials will become more negative over time. C. the production of action potentials will decrease quickly over time. D. None of the above.: C. the production of action potentials will decrease quickly over time. 18. 18. What happens to the membrane potential if the conductance for ion X increases, and the equilibrium potential of X is more positive than the resting potential? A. a depolarization. B. a hyperpolarization. C. No change. D. First answer B followed by answer A: A. a depolarization. 19. 19. Saltatory conduction of an action potential is ____ A. an example of increasing the speed of AP conduction by negative feedback. B. an example of increasing the speed of AP conduction by positive feedback.C. an example of increasing the speed of AP conduction by increasing the diameter of the axon. D. None of the above: D. None of the above 20. 20. Two neurons, A and B, synapse onto a third neuron, C. The A-C synapse is a chemical excitatory synapse and the B-C synapse is electrical. Which of the following statements is correct? A. An action potential in neuron A causes an IPSP in neuron B. B. An action potential in neuron B causes a depolarizing EPSP in neuron A. C. Simultaneous action potentials in A and B will cause less depolarization of neuron C than if only A firedan action potential. D. A depolarization in neuron C causes a depolarization in neuron B. E. A hyperpolarization in neuron C causes hyperpolarization in neuron A.: D. A depolarization in neuron C causes a depolarization in neuron B. 21. 21. In a myelinated axon, ___. A. Na that enters the cell at the cell body during an action potential is able to spread all the way to the axon terminal. B. Na enters the cell at the nodes of Ranvier during an action potential. C. neurotransmitter is released at nodes of Ranvier during an action potential. D. an action potential moves more slowly than in an unmyelinated axon. E. Answers A and C.: B. Na enters the cell at the nodes of Ranvier during an action potential. 22. 22. What is the correct sequence of events during an action potential? (1) membrane hyperpolarization, (2) activation of voltage dependent Na-channels, (3) deactivation of Na-channels and activation of voltage-dependent K-channels, (4) membrane depolarization, (5) deactivation ofK-channels and repolarization. A. 4 - 2 - 3 - 1 - 5 B. 5 - 4 - 1 - 3 - 2 C. 1 - 2 - 5 - 4 - 3 D. 2 - 3 - 5 - 1 - 4 E. 4 - 2 - 3 - 5 - 1: E. 4 - 2 - 3 - 5 - 1 23. 23. What will happen to the conduction velocity of action potentials if only the resistance across the axon membrane (rm) increases? A. An increase. B. A decrease. C. No change. D. A reversal of direction.: A. An increase. 24. 24. During the absolute refractory period _____ A. the Na-channels in the neural membrane cannot be opened. B. the neural membrane can produce another action potential with a full-sized amplitude. C. the neural membrane can produce another action potential with a re-duced-sized amplitude. D. Answers A and C.: A. the Na-channels in the neural membrane cannot be opened. 25. 25. The reversal potential differs from the action potential because the reversal potential ____ A. does not involve the Hodgkin Cycle. B. is due to opening of postsynaptic ion channels allowing simultaneous trans-port of both Na+ and K+ ions. C. reverses the direction of the Na+ ion flow across the membrane. D. Answers A and B. E. None of the above.: D. Answers A and B