1. True or false: at this moment, some of the muscle fibers in your gluteus maximus (a whole muscle) are contracting. a. True b.

Transcription

1 Exam III ANP 213 Spring 2008 You only need to print out the last two pages. Please do not consult classmates once you have begun this exam. Multiple Choice- 1 point each (use a ScanTron) 1. True or false: at this moment, some of the muscle fibers in your gluteus maximus (a whole muscle) are contracting. a. True b. False 2. Which muscle type is commonly directly influenced (can be induced to contract or relax) by conditions such as CO2 levels and hormones? a. Smooth muscle b. Cardiac muscle c. Skeletal muscle d. Fast-twitch muscle e. Slow-twitch muscle 3. Which of the following is false of glutamate: a. Post-synaptic receptors for glutamate are typically linked to K+ channels b. It is involved in learning and memory c. It typically affects post-synaptic cells directly d. Release of glutamate is associated with stroke e. It is used primarily by the central nervous system 4. Neurons of the CNS often form neuronal pools, networks of communication. Sometimes, a neuron sends a collateral back to its own dendrites, so that when it is excited it will continue to give itself EPSPs in a positive feedback loop. This type of system is called: a. Divergence b. Parallel processing c. Convergence d. Serial processing e. Reverberation 5. When a muscle contracts but does not change length, what type of contraction is it experiencing? a. Isotonic concentric b. Isotonic eccentric c. Isometric d. Anaerobic e. B and C

2 6. An action potential in skeletal muscle is restricted to one cell. In cardiac and some smooth muscle, action potentials begin in one cell and are spread among all cells. How is this type of conduction accomplished? a. Lack of insulating myelination b. Shared t-tubules c. Gap junctions between cells d. Lack of sarcomeres e. Neurotransmitter release from one cardiac muscle cell to the next 7. Which of the following is not true of cardiac muscle? a. Can be stretched substantially and still produce powerful contraction b. Uses primarily aerobic respiration c. Rate of contraction can be affected by neural input but contractions are self-initiated d. Myofibrils composed of sarcomeres e. Inhibited by the parasympathetic division of the ANS 8. Which of the following whole muscles would probably be composed of the smallest motor units? a. Rectus femoris (quadrucep, leg) b. Biceps brachii (upper arm) c. Pectoralis Major (chest) d. Medial Rectus (a muscle controlling eye movements) 9. Which of the following is NOT true of fast glycolytic fibers, relative to slow oxidative fibers? a. Less glycogen stores b. Fewer mitochondria c. More myofibrils d. Rely more on anaerobic pathways for ATP 10. Pacemaker cells in the heart depolarize spontaneously because a. They share gap junctions with other cardiac cells b. Ach is applied to them periodically from the parasympathetic division of the ANS c. They have more Na+ leak channels d. Na+ channels are timed and open spontaneously at a pace set by the parasympathetic division of the ANS

3 11. When an opioid is released onto a postsynaptic cell, the likely outcome is: a. Chemically-regulated Na+ channels will open b. Chemically-regulated K+ channels will open c. Receptors will start a chain of chemical reactions that will change the postsynaptic cell in some way 12. Ach is inhibitory to: a. Cardiac muscle b. Skeletal muscle c. Fast-twitch muscle d. Slow-twitch muscle 13. Of the following muscle types, which relies primarily on aerobic respiration, contains myofibrils, but does not reach complete tetanus: a. Smooth muscle b. Slow twitch muscle fibers c. Skeletal muscle d. Cardiac muscle 14. Smooth muscle cells can function even when stretched because: a. They are controlled by the Sympathetic division of the ANS b. They contract slowly c. The zones of overlap along the myofibrils are longer than in skeletal muscle d. The contractile proteins are arranged in such a way that they can maintain the zone of overlap 15. A resting muscle cell produces ATP primarily via pathways using the nutrient. a. Anaerobic; glucose b. Aerobic; glucose c. Anaerobic; fatty acids d. Aerobic; fatty acids 16. Which of the following is FALSE of somatic motor neurons: a. Secrete Acetylcholine onto skeletal muscle cells b. Are myelinated c. Are multipolar d. Have type B axon fibers e. Each controls more than one skeletal muscle cell at once

4 17. Which of the following is FALSE of neuron communication: a. Neurons that communicate often have various ways of becoming better at communicating, such as building more synapses together b. The effect of a neurotransmitter on a post-synaptic cell depends on the receptors of the post-synaptic cell c. Neurotransmitters travel from the presynaptic cell to the postsynaptic cell through gap junctions d. Often, a postsynaptic cell must experience temporal summation, spatial summation, or both, in order to be effectively brought to threshold 18. Typical skeletal and smooth muscle contraction involves: a. Twitch b. Treppe c. Complete tetanus d. Incomplete tetanus e. None of the above 19. When a muscle contracts and lengthens, what type of contraction is it experiencing? a. Isotonic concentric b. Isotonic eccentric c. Isometric d. Anaerobic e. B and C 20. A whole skeletal muscle can produce fast, very powerful contractions, and can sustain contractions for relatively long periods of time. It also has ample stores of myoglobin and glycogen. In addition, it has an extensive capillary network and lots of mitochondria. This muscle probably has lots of: a. Fast glyolyticfibers b. Slow oxidative fibers c. Intermediate (fast oxidative) fibers 21. Which of the following is NOT a characteristic of neurons? a. High metabolic rate b. Nissl bodies c. T-tubules bring ECF into the cell d. Conduct action potentials along an axon e. Use Ca2+ influx to trigger release of neurotransmitter

5 22. Receptors that monitor bone, joint and muscle position, and stretch are called: a. Interoceptors b. Exteroceptors c. Proprioceptors d. Interneurons e. Myelinated neurons 23. A neurotransmitter is produced in the cell body of a neuron. It will be moved from the cell body to the synaptic terminals along microtubules via: a. Anterograde flow b. Retrograde flow c. Action potentials d. EPSPs 24. Which of the following is NOT true of aerobic respiration: a. Occurs in mitochondria b. Requires oxygen c. Is slower to produce ATP than glycolysis d. Can provide ATP for extended periods of time e. Can only use glucose (cannot use fatty acids) to produce ATP 25. When a muscle fiber begins a contraction, what is the first source of ATP to be used? a. Stored ATP b. Creatine Phosphate c. Glycolysis d. Aerobic respiration e. Fatty acids 26. A neuron is structured such that the axon connects directly with the dendrites. Each (axon & dendrites) is clearly different. The cell body bulges off to the side. This neuron monitors stimuli from the outside world, and sends that information to the CNS. Its structure is and its function is. a. Bipolar; exteroceptor b. Unipolar; exteroceptor c. Multipolar; proprioceptor d. Anaxonic; interoceptor

6 e. Multipolar; interoceptor 27. The neuroglial cells that are responsible for creating the blood-brain barrier (control which substances can enter the brain from capillaries), and which provide structural support to the brain are: a. Astrocytes b. Oligodendrocytes c. Microglia d. Schwann cells e. Ependymal cells 28. In which of the following fiber types would the rate of impulse conduction be the greatest? a. Type A b. Type B c. Type C d. Type D 29. During saltatory conduction, a. Action potentials move in all directions along an axon b. Action potentials occur at successive nodes along the length of the axon c. Graded potentials summate to produce an action potential d. Action potentials fizzle out midway down the axon and do not reach the terminals. 30. If a neurotransmitter caused an EPSP on a post-synaptic cell, it might a. Cause Na+ channels to open b. Cause K+ channels to open c. Cause Cl- channels to open d. Cause Na+ channels to close e. Any of the above are possibilities 31. The effect (excitatory vs. inhibitory) of a neurotransmitter on a postsynaptic cell is determined by: a. The neurotransmitter s chemical structure b. Enzymes in the synaptic cleft c. IPSPs d. The types of receptors present on the postsynaptic cell

7 32. The muscle type/s served by the Autonomic Nervous System is/are: a. Smooth muscle b. Cardiac muscle c. Skeletal muscle d. A and B e. B and C 33. Which of the following neurons would have the fastest rate of conduction: a. Myelinated, 20 microns in diameter b. Nonmyelinated, 20 microns in diameter c. Myelinated, 2 microns in diameter d. Nonmyelinated, 25 cm in length 34. If a Nt exerts indirect effects on a postsynaptic cell, a. It causes Na+ or K+ channels to open immediately b. It causes a chain reaction of chemical events in the postsynaptic cell that will somehow change that cell s responsiveness to other Nt (for example, cause the postsynaptic cell to build more channels). c. It will have long-term effects on the postsynaptic cell d. B and C e. All of the above 35. Which of the following is FALSE of slow oxidative fibers relative to fast oxidative fibers: a. More myoglobin b. More myofibrils c. More mitochondria d. More extensive capillary network e. None of the above are true of slow oxidative fibers. 36. The division is a branch of the Autonomic Nervous System, which in turn is a branch of the division of the Peripheral Nervous System. a. Central Nervous; Afferent b. Parasympathetic; Somatic c. Somatic; Sympathetic d. Efferent; Sympathetic e. Parasympathetic; Efferent 37. The neuroglial cells that myelinate neurons of the Peripheral Nervous system are: a. Astrocytes b. Microglia

8 c. Schwann cells d. Oligodendrocytes e. Satellite cells 38. Smooth muscle cells can function even when stretched because: a. They are controlled by the Sympathetic division of the ANS b. They contract slowly c. The zones of overlap along the myofibrils are longer than in skeletal muscle d. The contractile proteins are arranged in such a way that they can maintain the zone of overlap 39. A resting muscle cell produces ATP primarily via pathways using the nutrient. a. Anaerobic; glucose b. Aerobic; glucose c. Anaerobic; fatty acids d. Aerobic; fatty acids 40. The period beginning when the activation gates of voltage-regulated sodium channels along an axon open, and ending when both gates return to normal, is called the. During this time, the neuron respond to another stimulus. a. Relative refractory period; cannot b. Relative refractory period; is less likely to c. Absolute refractory period, cannot d. Absolute refractory period; is less likely to 41. An action potential travels along an axon toward synaptic terminals. Which of the following does NOT happen as an eventual consequence of the action potential reaching the terminal? a. Voltage-regulated Ca2+ channels open b. Ca2+ enters the cell c. Neurotransmitter is released by exocytosis d. Voltage-regulated channels open, through which neurotransmitter leaves the cell

9 42. A neuron may be brought to threshold by: a. Spatial summation b. Temporal summation c. IPSPs d. A and B e. All of the above 43. A neuron is facilitated if it is: a. Depolarized b. Hyperpolarized c. At resting potential 44. Motor neurons to skeletal muscle contain fibers (axons): a. Type A b. Type B c. Type C d. Type D 45. The role of Creatine Phosphate in muscle cells is to: a. Reattach ADP to PO4 in the beginning stages of a contraction b. Store O2 for aerobic respiration c. Be split into two pyruvates during glycolysis d. Hydrolyze (break up) Ach e. Release Ca If you wanted to bring a muscle cell to incomplete tetanus in the lab, you would shock it or apply Ach to it during the phase: a. Latent b. Contraction c. Relaxation d. Hyperpolarization 47. When glutamate is released onto a postsynaptic cell, the likely outcome is: a. Chemically-regulated Na+ channels will open b. Chemically-regulated K+ channels will open c. Receptors will start a chain of chemical reactions that will change the postsynaptic cell in some way

10 48. Which of the following neurotransmitter types is known to be important for physical pain reduction? a. NorEpinephrine b. Carbon Monoxide c. Serotonin d. Opioids e. Glutamate 49. On a type A neuron fiber, where would I find voltage-regulated sodium channels? a. Dendrites b. Nodes of Ranvier c. Schwann cells d. Continuously along the axon e. Microtubules 50. Which of the following is FALSE of K+ (potassium)? a. Efflux repolarizes muscle cells and neurons b. Efflux hyperpolarizes neurons c. The sodium-potassium exchange pump uses ATP to pull 2 K+ in the cell for every 3 Na+ it puts out d. If a neurotransmitter binds to a receptor that causes a K+ gate to open on a post-synaptic neuron, the post-synaptic neuron will experience an EPSP e. There are more K+ leak channels along axons than Na+ leak channels; this phenomenon is part of what maintains the resting electrochemical gradient 51. Which of the following is NOT a characteristic of neurons? a. Longevity b. Inability to divide c. High metabolic rate d. Ability to survive without oxygen 52. Which of the following does NOT occur as the skeletal muscles enlarge (hypertrophy) in a weight lifter: a. The muscle cells divide mitotically b. The muscle cells grow larger c. Myofibrils become more abundant in the muscle cells d. Neither B nor C occur during muscle hypertrophy e. All of the above occur during muscle hypertrophy

11 53. The type of muscle fiber that has no myofibrils is: a. Skeletal b. Smooth c. Cardiac d. Fast glycolytic e. Slow oxidative 54. Which of the following is the correct path an impulse takes across a synapse? a. Axon of postsynaptic neuron, dendrite of presynaptic neuron, clft b. Dendrite of presynaptic neuron, cleft, axon of postsynaptic neuron c. Axon of presynaptic neuron, cleft, dendrite of postsynaptic neuron d. Cleft, dendrite of postsynaptic neuron, axon of presynaptic neuron e. None of the above 55. A node of Ranvier a. Occurs only in ganglia b. Is one segment of the myelin sheath c. Occurs in the PNS but not in the CNS d. Is a bare region of axonal membrane in myelinated axons only e. Is the region of a neuron that must reach threshold voltage in order for an action potential to begin 56. Vesicles containing neurotransmitters are located in: a. A synaptic cleft b. Axon terminals c. The postsynaptic region of dendrites d. The nodes of Ranvier e. Nissl bodies 57. Which of the following is FALSE of all 3 types of muscle contraction (smooth, skeletal, and cardiac): a. Ca2+ influx from the SR initiates the contraction b. Myosin heads bind active sites (myosin binding sites) on actin c. Muscle shortening involves thin fibers moving toward the M-lines of sarcomeres d. A zone of overlap must exist in order for the contraction to occur e. Thin fibers and thick fibers shorten as the muscle is contracting, and elongate as the muscle relaxes

12 58. One of the largest and strongest whole muscles in the body is the gluteus maximus in the buttocks; it is important in walking, running and climbing stairs. It consists of: a. Slow oxidative fibers only b. Fast glycolytic fibers only c. Fast oxidative fibers only d. A mixture of fiber types 59. After a muscle fiber has contracted, the calcium: a. Is destroyed b. Is bound to the myofilaments c. Is secreted by the Golgi apparatus via exocytosis d. Re-enters the sarcoplasmic reticulum e. Diffuses out of the cell through leak channels 60. The immediate result of Ca2+ release from the sarcoplasmic reticulum is: a. Myosin heads are recocked b. The cell experiences an action potential c. Tropomyosin is removed from actin binding sites d. Na + channels open at the motor end plate e. Na+ channels open along the t-tubules 61. Which of the following processes can sustain muscle cell activity for the longest period of time, and where does it occur: a. Hydrolysis of CP; near contractile proteins b. Glycolysis; in cytosol c. Aerobic respiration; in cytosol d. Glycolysis; in mitochondria e. Aerobic respiration; in mitochondria 62. Which of the following is NOT a role of Ca2+: a. Stimulate release of neurotransmitter from synaptic terminals b. Participate in bone structure c. Cause hyperpolarization of excitable membranes (ex., neurons & muscle cells) d. Allow contraction of muscle cells e. A and D

13 Matching: use your ScanTron, 1 point each Match the following neuroglia with their functions: 63. Schwann cells a. Maintain the ECF of the CNS 64. Ependymal cells b. Myelinate axons of the PNS 65. Microglia c. Myelinate axons of the CNS 66. Oligodendrocytes d. Produce cerebrospinal fluid e. Phagocytize debris in the CNS Match the following aspects of calcium with the correct cell types/hormones (use the ScanTron to indicate your answers) Aspect of Calcium Cell type or hormone 65. Stored in the SR a. neuron only 66. Causes synaptic vesicles to release b. skeletal muscle cell only Nt 67. Comes from the ECF c. both neuron and skeletal muscle cell 68. Pumped back to SR or ECF via d. PTH active transport 69. Passively diffuses back to the SR or e. none of the above ECF 70. Increases osteoclast activity; increases blood calcium 71. Ca++ channels open as a result of action potentials

14 Short Answer 72. Describe what happens with voltage-regulated sodium and potassium channels along an axon during an action potential in a neuron. Mention important voltages and what happens to the Na+ and K+ channels at those important voltages. How do these events affect the movement of Na+ and K+; that is, when are Na+ and K+ allowed to move into and out of the cell through these channels? In your answer, use the terms: depolarization, hyperpolarization, repolarization, threshold, activation gate, inactivation gate Be sure to present your answer in a clear, logical time sequence.

15 73. As you're relaxing, a lion comes crashing through your window (you're in Africa and the prey population has been low this year). You leap up, rip the bookcase from the wall and throw it in his path, and sprint as fast as you can but get tired out by the time you reach the kitchen. a) How (what process) do you think your quadruceps are producing ATP? b) What muscle type (fast, slow, or intermediate). is probably dominating your actions (sprinting and tearing down bookcases) and describe 5 characteristics of that type of muscle fiber c) Why was the contraction in your biceps stronger as you pulled down the bookcase than it was when you calmly removed a book earlier (other than a difference in fiber type)? d) What nutrient are the contracting fibers in your quadruceps probably using for energy? Bonus (.5 each) -Name one area where neural stem cells persist into adulthood. -What vitamin is particularly important for production and maintenance of the myelin sheath?