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Electrophysiology and Neural Tissue review questions 1. Microglial cells produce myelin in the central nervous system (True/False) Oligodendrocytes produce myelin in the CNS 2. Cells become more negative during hyperpolarization. (True/False) 3. Leak sodium channels are the primary determinant...

Electrophysiology and Neural Tissue review questions 1. Microglial cells produce myelin in the central nervous system (True/False) Oligodendrocytes produce myelin in the CNS 2. Cells become more negative during hyperpolarization. (True/False) 3. Leak sodium channels are the primary determinant of the resting membrane potential of a neuron (True/False) Leak potassium channels are the primary determinant of the resting membrane potential 4. The parasympathetic nervous system is considered part of the afferent portion of the peripheral nervous system (True/False) parasympathetic nervous system is considered part of the efferent portion 5. Terminal buttons of neurons release neurotransmitters (True/False) 6. Action potentials will travel in both directions from the middle of a motor neuron (True/False) The refraction of the membrane cause the AP to travel only towards the terminus (one direction) 7. Larger diameter neurons will propagate action potentials at a slower velocity compared to smaller diameter neurons (True/False) Larger diameter neurons have faster velocity of propagation 8. Voltage-gated potassium channels cause the rapid upstroke of an action potential (True/False) Voltage-gated sodium channels cause the rapid upstroke 9. The afterhyperpolarization phase of an action potential is due to current moving through voltage-gated potassium channels (True/False) 10. Activation of ligand gated Cl- channels by neurotransmitters in the synaptic cleft with typically lead to EPSP’s (True/False). Activation of ligand gated Cl- channels most often cause IPSPs 11. The “tightness” of the blood-brain barrier results mostly from the action of __________, a type of glial cell. A. ependymal cells B. microglia C. astrocytes D. oligodendrocytes 12. The sodium equilibrium potential using an extracellular Na+ concentration of 145 mEq/L and an intracellular concentration of 14 mEq/L would be about A. -90mV. B. +62mV. C. -62mV. D. +90mV 13. The resting membrane potential is closest to the equilibrium potential for: A. sodium ions. B. chloride ions. C. calcium ions. D. potassium ions. 14. Hyperkalemia would _______resting membrane potential of the cell. A. increase (more positive) B. decrease (more negative) C. have no effect on 15. Neurotransmitter release would be inhibited by: A. stimulating repolarization of the axon terminal. B. blocking Ca2+ influx in the axon terminal. C. blocking repolarization of the axon terminal. D. stimulating protein kinase activity Electrophysiology and Neural Tissue review questions 16. What is NOT true of the relative refractory period? A. Na+ channels are inactivated ( the sodium channels are reset and ready to go during the relative refractory period) B. many Na+ channels are returning to a closed state C. K+ is moving out of the axon through its open channels D. a strong stimulus could cause a depolarization 17. Chemicals that stimulate action potentials in postsynaptic cells are called: A. hormones. B. enzymes. C. neurotransmitters. D. neurotrophins. 18. What action produces an IPSP on the postsynaptic membrane (choose all that apply)? A. influx of Na+ ions B. opening of Ca2+ channels into the neuron C. outflow of K+ ions D. opening of Cl- channels into the neuron Muscle questions 1. During skeletal muscle contraction the A band decreases in size (True/False) False (no change) 2. Increasing the frequency of action potentials in a somatic motor neuron will induce increased force of muscle contraction. (True/False) True 3. Thin filaments are composed of myosin and tropomyosin (True/False) False (actin) 4. Cross-bridge formation occurs when myosin heads attach to actin molecules located in the thin filaments (True/False) True 5. Smooth muscle contraction requires the actions of myosin light chain kinase (True/False) True 6. Transverse tubules contain voltage-gated calcium channels that respond to membrane depolarization and are directly coupled to the calcium release channels in the sarcoplasmic reticulum. (True/False)True (we described the DHP as a receptors rather than a channel but they act as voltage gated channels 7. Ca2+ must bind to tropomyosin so that the myosin binding sites on actin will be accessible to the myosin. (True/False) False (troponin) 8. The deadly botulinum toxin can be used in the cosmetic treatment of skin wrinkles because it produces a flaccid paralysis. (True/False) True 9. The light band of a skeletal muscle is known as the A. A band. B. Z disc. C. I band. D. H zone. 10. The specialized region of the sarcolemma at the neuromuscular junction is called the A. syncytium. B. varicosity. C. fascicle. D. motor end plate. 11. Motor unit recruitment allows for _________ contraction strength. A. increased B. decreased C. no change in 12. Somatic motor neurons release the neurotransmitter _________ at the neuromuscular junction. A. dopamine B. acetylcholine C. norepinephrine D. serotonin 13. Each somatic motor neuron with all the muscle fibers it innervates is a A. fascicle. B. varicosity. C. motor unit. D. sarcolemma. 14. What structure is composed of protein filaments and is located in the center of the thick filaments? A. Z disk Muscle questions B. titin C. M line D. actin 15. What muscle structural and functional unit runs from Z disc to Z disc? A. A band B. I band C. sarcomere D. myofibril 16. The thick filament is also called the A. A band. B. I band. C. H zone D. M line 17. What protein primarily makes up the thick filament? A. actin B. myosin C. titin D. troponin 18. Myosin contains binding sites for ______________ and _____________. A. sodium, calcium. B. troponin, ATP. C. ATP, actin. D. actin, calcium 19. What activates the myosin head to begin cross-bridging? A. release of Pi B. binding of ATP to the head C. splitting of ATP into ADP and Pi D. addition of Ca2+ to the head 20. ________ is characterized by continued attachment of myosin heads to actin filaments due to a lack of ATP. A. Tetanus B. Rigor mortis C. Flaccid paralysis D. Treppe 21. During skeletal muscle contraction, A. the H zone increases in size. B. Ca2+ associates with tropomyosin. C. myosin heads interact with tropomyosin. D. thin filaments slide across thick filaments. Muscle questions 22. Which molecule blocks the myosin head from binding to actin in a relaxed muscle? A. tropomyosin B. troponin C. calcium D. titin 23. The _________ complex contains three proteins designated as the I, T, and C types. A. actin B. myosin C. tropomyosin D. troponin 24. The pumps that actively transport calcium back into the _______ are called Ca2+ -ATPase pumps. A. transverse tubules B. sarcoplasmic reticulum C. neuromuscular junction D. None of the choices are correct. 25. What structures carry the action potentials into the interior of the muscle to cause muscle contraction? A. T tubules B. terminal cisternae C. sarcoplasmic reticula D. ryanodine receptors 26. What is the role of ATP in muscle contraction and relaxation? A. It is hydrolyzed for myosin head to attach to actin. B. It causes myosin head to detach from actin. C. It powers the Ca2+ pumps to return Ca2+ to the SR. D. All of the choices are correct. 27. Which of the following statements regarding cardiac muscle is true? A. Dense bodies anchor thin filaments. B. Fibers lack I and A bands. C. Intercalated discs contain gap junctions. D. Fibers lack branches. 28. _________ filaments are attached to dense bodies in smooth muscle cells. A. Actin B. Myosin C. Troponin D. Tropomyosin Muscle questions 29. Smooth muscle cells A. contain intercalated discs. B. contain A and I bands. C. are innervated by somatic nerves. D. may contain gap junctions. 30. What condition of smooth muscle allows it to maintain contraction for long periods of time? A. latch state B. gap junctions C. peristalsis D. myogenic activity The Autonomic Nervous System and muscle questions: Answer Key 1. Autonomic motor pathways utilize two neurons while somatic motor pathways utilize one neuron (True/False) 2. Postganglionic sympathetic neurons arise from the thoracic and lumbar regions of the spinal cord. (True/False) Preganglionic sympathetic neurons arise from the thoracic and lumbar regions 3. Destruction of the celiac ganglia would inhibit sympathetic regulation of the adrenal glands. (True/False) 4. Postganglionic parasympathetic fibers are relatively long (True/False) Postganglionic parasympathetic fibers are relatively short 5. The adrenal medulla is a modified sympathetic ganglion that secretes epinephrine when stimulated by sympathetic preganglionic neurons. (True/False) 6. The vagus nerve gives rise to preganglionic parasympathetic fibers involved in regulating most thoracic and abdominal organs. (True/False) 7. Sympathetic stimulation of an organ ALWAYS opposes the effects of parasympathetic stimulation. (True/False) Some organs are only innervated by sympathetic and some organs the like the salivary glands the responses are not the opposite 8. Fibers that secrete norepinephrine are called adrenergic fibers (True/False) 9. Heart rate is increased in response to sympathetic stimulation (True/False) 10. Fibers that secrete acetylcholine are called cholinergic fibers (True/False) 11. Adrenergic receptors are found on the surface of postganglionic sympathetic neurons (True/False) nAchR’s are found on the surface of postganglionic sympathetic nerves 12. Organs innervated by autonomic motor neurons are often under voluntary control. (True/False) Involuntary control 13. Salivary secretions are decreased and become thicker in response to sympathetic stimulation. (True/False) 14. Autonomic motor nerves do NOT innervate: A. smooth muscle B. skeletal muscle C. cardiac muscle D. glands 15. Somatic motor neurons have a direct connection between the CNS and their effector organs while ______________ motor neurons must synapse on with a peripheral neuron before reaching their effectors. A. Skeletal B. Sensory C. Autonomic D. Both skeletal and autonomic are correct 16. Damage to the autonomic motor nerves would probably result in: A. No change in skeletal muscle tone B. Muscle atrophy C. Flaccid paralysis D. Increased skeletal muscle contraction The Autonomic Nervous System and muscle questions: Answer Key 17. Where do autonomic preganglionic neurons originate? A. midbrain (part of the brainstem) B. hindbrain (part of the brainstem) C. thoracic and sacral regions of the spinal cord D. All of the choices are correct. 18. Where do autonomic postganglionic neurons originate? A. Hindbrain B. gray matter of spinal cord C. peripheral ganglia D. All of the choices are correct 19. ____________ fibers have relatively slower nerve conduction because they are thin and unmyelinated. A. Preganglionic autonomic sympathetic B. Postganglionic autonomic sympathetic C. Preganglionic somatic D. Postganglionic somatic 20. Where do parasympathetic preganglionic neurons originate? A. Brainstem B. thoracic and lumbar region of the spinal cord C. sacral region of the spinal cord D. brainstem and sacral region of the spinal cord 21. Cutaneous effectors such as blood vessels, sweat glands, and erector pili muscles are innervated by A. only parasympathetic nerves. B. only sympathetic nerves. C. both parasympathetic and sympathetic nerves. D. both parasympathetic and somatic nerves. 22. The parasympathetic division of the autonomic nervous system A. has long postganglionic neurons. B. has a single neuron arising from the spinal cord. C. has relatively short preganglionic neurons. D. has terminal ganglia embedded in the visceral effectors 23. The vagus nerve would innervate all of the following except A. the heart. B. the stomach. C. the liver. D. the iris. The Autonomic Nervous System and muscle questions: Answer Key 24. Which autonomic division is dominant in an emergency situation? A. sympathetic B. parasympathetic 25. Which autonomic division is dominant in normal body functions such as digestion? A. sympathetic B. parasympathetic 26. Bright light would stimulate regulation of pupil diameter through _____________ nerves. A. sympathetic B. parasympathetic C. somatic D. sensory 27. The parasympathetic division of the autonomic nervous system A. utilizes norepinephrine as a postganglionic neurotransmitter. B. has a relatively short preganglionic neuron. C. utilizes acetylcholine as a preganglionic neurotransmitter. D. includes the adrenal medulla.. 28. _____________ is released by most postganglionic sympathetic nerves. A. Acetylcholine B. Epinephrine C. Norepinephrine D. Dopamine 29. The _____________ has both 1 and 1 receptors and responds to sympathoadrenal stimulation with glycogenolysis and secretion of glucose. A. liver B. pancreas C. adrenal cortex D. None of the choices are correct. 30. Blocking 2-adrenergic receptors prevents airway A. constriction. B. dilation. 31. Phenylephrine functions as a _______ because it promotes vasodilation in nasal mucosa. A. 1 agonist. B.  a1 antagonist. C. 1 agonist. D. 1 antagonist. The Autonomic Nervous System and muscle questions: Answer Key 32. M2 receptors in the heart A. decrease heart rate. B. increase heart rate. C. cause increased cytosolic Ca2+ in heart cells. D. cause increased spontaneous depolarization in the heart. 33. Atropine would A. block the release of epinephrine from the adrenal medulla. B. block constriction of the pupil. C. stimulate skeletal muscle contraction. D. facilitate near vision. 34. Which of the following organs is dually innervated? A. adrenal medulla B. erector pili muscles in the skin C. urinary bladder D. most blood vessels True / False Questions 1. Cardiac output increases as heart rate increases. True 2. Under resting conditions, all of the body's blood is pumped through the left ventricle in one minute. (True, CO 5 l/min and the body has about 5 liters) 3. The ventricles pump an average of 50-60 mL of blood per minute. False, this is the stroke volume which occurs per contraction 4. EDV is the amount of blood in the ventricles right before they begin to contract. True 5. At rest, most blood is within the venous system. True 6. Edema may result from increased plasma protein concentrations False, increase plasma proteins would decrease filtration and decrease edema 7. Hypertension increases afterload, making it more difficult for the ventricles to eject blood. True 8. Parasympathetic stimulation of arterioles is a major contributor to total peripheral resistance. False, only sympathetic 9. Cardiac output is equal to A. stroke volume - cardiac rate. B. stroke volume / cardiac rate. C. stroke volume + cardiac rate. D. stroke volume x cardiac rate 10. Norepinephrine is released from __________ nerves, causing heart rate to ______. A. parasympathetic, increase. B. parasympathetic, decrease. C. sympathetic, increase. D. sympathetic, decrease. 11. Norepinephrine and epinephrine open ____ channels inducing a faster diastolic depolarization. A. voltage-gated Ca2+ B. fast Ca2+ C. F-type Na+ D. fast Na+ 12. What type of receptors do norepinephrine and epinephrine bind to in the heart? A. 1-adrenergic B. -adrenergic C. muscarinic D. nicotinic 13. Acetylcholine binds to _______ receptors of the heart and causes the opening of ___ channels. A. muscarinic, K+ B. nicotinic, K+ C. muscarinic, Na+ D. nicotinic, Na+ 14. The effect of acetylcholine binding to its receptors in the heart is a heart rate A. increase. B. decrease. C. unchanged. 15. Sympathetic stimulation of the heart will A. increase the rate of diastolic depolarization. B. increase conduction rate. C. increase the strength of contraction. D. All of the choices are correct. 16. The volume of blood in the ventricles at the end of diastole is known as the A. after-load. B. pre-diastolic volume (PDV). C. stroke volume (SV). D. end-diastolic volume (EDV). 17. Venous return is increased by all of the following EXCEPT A. exhalation. B. the skeletal muscle pump. C. hypertension. D. sympathetic stimulation of the veins. 18. Net filtration would be decreased by A. liver damage. B. increased hepatic protein synthesis. C. hypotension. (not the best answer because the myogenic response would hopefully maintain Pc and NFP) D. increased cellular metabolism. 19. Edema would be induced by all of the following EXCEPT A. hypertension. B. protein malnutrition. C. lymphatic blockage. D. decreased capillary pressure 20. Elephantiasis is caused by A. decreased plasma protein concentration. B. obstruction of lymphatic drainage. C. high arterial blood pressure. D. myxedema. 21. What is the main force that causes fluids to enter the venous end of a capillary? A. hydrostatic pressure in the capillary B. hydrostatic force in the interstitial fluid C. colloid osmotic pressure in the capillary (blood plasma) D. colloid osmotic pressure in the interstitial fluid 22. Increased blood flow resistance is caused by A. increased blood vessel length. B. decreased blood viscosity. C. vasodilation. D. increased blood pressure. 23. Vascular smooth muscle can directly respond to changes in pressure. This type of control is called A. metabolic. B. extrinsic. C. vasogenic. D. myogenic. 24. Vasodilation is induced by all of the following EXCEPT A. increased tissue carbon dioxide. B. decreased tissue metabolism. C. decreased tissue oxygen. D. increased extracellular K+. 25. Reactive hyperemia is A. increased blood flow due to increased metabolism. B. increased blood flow after removal of constriction due to accumulated metabolic products. C. increased blood flow due to sepsis. D. All of the choices are correct 26. Active hyperemia is A. increased blood flow due to increased metabolism. B. increased blood flow after removal of constriction due to accumulated metabolic products. C. increased blood flow due to sepsis. D. All of the choices are correct. 27. Control of blood flow to skeletal muscles during exercise is mainly under _______ control. A. intrinsic metabolic B. intrinsic myogenic C. extrinsic D. hormonal 28. Cardiovascular changes resulting from moderate exercise include A. increased total peripheral resistance. B. increased blood flow to the skin. C. increased visceral blood flow. D. decreased stroke volume. 29. During exercise, all of the following occur EXCEPT A. increased stroke volume. B. increased cardiac rate. C. shunting of blood from visceral organs to skeletal muscle and heart. D. increased vasoconstriction of coronary arteries. 30. Arterial blood pressure is influenced by A. vasoconstriction. B. cardiac rate. C. cardiac output. D. All of the choices are correct. 31. If cardiac output increases, the peripheral resistance must _____ for arterial blood pressure to remain constant. A. increase B. decrease C. no change 32. Which blood vessels have the highest cross-sectional area? A. veins B. arterioles C. venules D. capillaries 33. Which blood vessels have the lowest pressure? A. veins B. arterioles C. venules D. capillaires 34. Inhibition of the baroreceptor reflex would not allow for proper regulation of all but A. cardiac rate. B. stroke volume. C. respiratory rate. D. blood pressure. 35. Increased blood pressure stimulates A. decreased outflow from the baroreceptors. B. decreased sympathetic outflow to the heart. C. decreased parasympathetic outflow to the heart.