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EXAM 2 - 50 Questions
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Bio3200: Human Physiology Oct. 18, 2022 EXAM 2 [50 Qs + 3 extra credit]
Section 1: Complete each sentence with one of the two words in square brackets [A. /B. ].
- Loads are moved by [A. isometric/B. isotonic] contractions.
- Phosphorylation of myosin light chains in smooth muscle is associated with a/an [A. increase/ B. decrease] in contraction.
- Isovolumetric ventricular contraction is most closely associated with the [A. QRS complex /B. T-‐ wave].
- Motor neurons are sometimes inhibited by [A. muscle spindle/B. Golgi tendon organs] originating from the muscle it innervates.
- The [A. z-‐line/B. M-‐line] is the structure that marks the boundary between sarcomeres.
- The [A. parasympathetic/B. sympathetic] branch is characterized by a chain of ganglion running along side of the spinal cord.
- Given dual innervation by autonomic neurons, if sympathetic activity inhibits pancreatic secretion, parasympathetic activity should [A. inhibit/B. stimulate] pancreatic secretion.
- Most reflex movements are integrated by [A. the somatosensory cortex/B. the spinal cord].
- In a given capillary bed, [A. vasodilation/B. vasoconstriction] will occur when local metabolism increases.
- As the total cross-‐sectional area of blood vessels in an organ increases, the velocity of blood through that organ [A. increases /B. decreases].
- A single muscle cell is also called a [A. muscle fiber/B. myofibril].
- For a muscle to change from unfused tetany to fused tetany, the stimulus frequency must [A. increase/B. decrease].
- The [A. preganglionic/B. postganglionic] neuron has its cell body in a ganglion.
- Autonomic nervous system control of arteriolar resistance is an example of [A. antagonistic /B. tonic] control.
- The depolarization of the pacemaker action potential spreads to adjacent cells through [A. gap/B. tight] junctions.
Section 2: Multiple Choice. Select single best answer based on Physiology.
- Thinking about higher order motor control, which of the following is NOT matched correctly? A. cerebellum ; co-‐ordination and timing B. propriceptors ; detection of limb position. C. corticospinal tract ; postural reflex control. D. basal ganglion ; motor subroutine planning E. pre-‐frontal cortex ; planning and decision making
- In the cardiac cycle, leads to , which in turn leads to and therefore. A. repolarization ; relaxation ; blood flow ; change in pressure B. depolarization ; change in pressure ; blood flow ; muscle contraction C. depolarization ; muscle contraction ; change in pressure ; blood flow D. repolarization ; muscle contraction ; blood flow ; change in pressure E. contraction; depolarization ; change in pressure ; blood flow
- The following is a diagram of the NMJ and a muscle depicting aspects of excitation-‐contraction coupling. mn = motor neuron; T-‐t = T-‐tubule; SR =sarcoplasmic reticulum. Based on this diagram, which of the following statements is TRUE?
A. a Ca2+-‐ATPase is located at position 3 B. voltage-‐gated K+ channels can be found in many places including positions 1, 3 and 7. C. ligand-‐gated K+ channels are present at position 2. D. voltage-‐gated Na+ & K+ channels at position 1 are used to propagate a muscle action potentials. E. a mechanically gated calcium release channel is present at 6.
- In order for blood to enter the heart, A. the atria must be in diastole. B. the pressure in the atria must be lower than in the veins. C. the AV valves must be closed. D. A and B E. A, B and C
- The mean arterial pressure (MAP) is important because A. it represents the pressure at the peak of blood ejection from the heart. B. it represents the volume of blood flow. C. it represents the pressure of the pulmonary vein. D. it reflects the difference in time that systole lasts compared to diastole. E. it represents the driving force for blood flow.
- A drug G inhibits parasympathetic activity. If administered to an experimental animal, it will do what to the cardiovascular system? A. decrease diameter of arteries B. increase diameter of veins C. decrease heart rate D. increase stroke volume E. increase heart rate
- Each of the following changes will result in increased blood flow to a tissue EXCEPT: A. decreased vessel diameter B. relaxation of precapillary sphincters C. increased blood pressure D. decreased peripheral resistance E. increased blood volume
- Which of the following comparison of muscle types is INCORRECT? A. Smooth and cardiac muscle contraction, but not skeletal muscle, are under the control of the autonomic nervous system. B. T-‐tubules are present in skeletal and cardiac muscle, but not in smooth muscles. C. Skeletal and cardiac muscle are characterized by thick filament regulation, while smooth muscle uniquely uses thin filament regulation. D. All three muscle types utilize Ca2+ from the SR (also called the ER), although the mechanism of release is different. E. Like smooth muscle cells, some cardiac myocytes have pacemaker potentials, but skeletal muscle does not.
- Muscle fatigue A. is only driven by central components B. may involve a decrease inactivity of ACh esterase C. may involve accumulation of calcium ions around myosin. D. may involve the degree of ACh release from the motor neuron E. is a non-‐reversible condition
- Put these events in the correct chronological sequence:
- Muscle action potentials are initiated.
- Transverse tubules convey potentials into the interior of the cell.
- Myosin dependent contractile cycles begin.
- End plate depolarizes as sodium ions enter.
- Ca2+ is released from the sarcoplasmic reticulum.
- Acetylcholine binds to receptors on the motor end plate.
- Ca2+ ions bind to troponin, pulling on tropomyosin A. 4, 5, 1, 7, 2, 6, 3 B. 3, 6, 1, 2, 5, 7, 4 C. 3, 6, 1, 5, 7, 2, 4 D. 6, 5, 2, 1, 4, 7, 3 E. 6, 4, 1, 2, 5, 7, 3
- The following is a representation of 9 different motor units (mu) from a single gross muscle (un-‐ mixed) in the arm. Tension per mu is shown on y-‐axis, while x-‐axis is frequency of action potentials. Strictly there are 9 axis -‐ one for each mu -‐ but here they are collapsed onto one X-‐axis (as discussed in class). Based on this diagram which of the following statements is FALSE?
A. asynchronous firing of mu 7, 8, and 9 will allow the development of 2 units of tension for a long period of time. B. maximum firing of mu 1, 2 and 4 will yield 6 units of tension, but fatigue rapidly C. regulated firing of both mu 5 and 6 together can yield a tension of 3 units. D. regulated firing of mu 3 and 4 together can yield a range of tension from 1 to 12 units worth. E. full activation of this gross muscle will yield a maximum tension of 38 units.
- After stretching an intrafusal fiber, the next event is A. a decrease in muscle tone. B. decreased sensitivity to stretching. C. a decrease in muscle tension. D. a contraction of the muscle spindle. E. an increase in action potentials along the associated sensory neuron.
- Arterioles participate in which of the following functions: A. help regulate mean arterial pressure B. convert the pulsatile nature of arterial blood pressure into a smooth, non-‐ fluctuating pressure in the vessels further downstream C. act as the main determinant of total peripheral resistance D. A and C E. A, B and C
- Which of the following is INCORRECT? A. All post-‐ganglionic axons end with varicosities. B. The autonomic nervous system is composed of pre-‐ and post-‐ganglionic neurons, C. The adrenal medulla is a modified parasympathetic ganglion with chromaffin cells secreting hormone into the blood. D. Autonomic ganglion can be involved in modulating and integrating information. E. Varicosities have the ability to secrete neurotransmitter and allow action potentials to pass through them to the next one.
- The following is a diagram of the 1A afferent coming into the dorsal horn of a spinal cord from a muscle spindle (only half of the cord is shown). An interneuron (z) is shown as are two motor neurons (mnA & mnB). Based on the connectivity of this synaptic system
A. mnA will lead to the extrafusal fibers of the same muscle as the 1A afferent B. mnB will lead to the extrafusal fibers of the same muscle as the 1A afferent C. the interneuron Z must be an inhibitory interneuron D. A and C E. B and C
- Which of the following is NOT a property of single-‐unit smooth muscles? A. Each cell functions independent of its neighbor. B. Only a proportion of the smooth muscle cells receive autonomic nervous input. C. Electrical responses travel directly between cells. D. All smooth muscle cells are connected by gap junctions. E. Their contraction occurs in a coordinated manner.
- The following is a schematic of the ANS similar to your textbook. The black box at the far right is a target organ, while the dotted box at left represents the CNS. Based on this schematic, which of the following statements is TRUE?
A. The cell body at D is in the dorsal root ganglion. B. The transmitter at both A and C is Acetylcholine. C. The pathway of neurons A and B represents the pathway to the adrenal medulla. D. The neurotransmitter at B is norepinephrine. E. The muscarinic receptor binds to the transmitter released at E.
- You and your lab partner use a living nerve and muscle preparation to study muscle contraction and were asked to investigate how drug ZZ might be working. Based on the following seven (7) experimental outcomes, what is the most likely effect of ZZ?
- If you electrically stimulate the nerve the muscle contracts.
- If you electrically stimulate the muscle directly it contracts.
- Drug TTX, which inhibits voltage-‐dependent Na+ channels, blocks contraction with either nerve or muscle stimulation.
- Inhibiting ACh-‐Rs with curare blocks muscle contraction with nerve but not muscle stimulation.
- If you apply drug ZZ to the preparation (with no other reagent or stimulus) the muscle contracts.
- If you add both curare and ZZ the muscle contracts.
- If you add both TTX and ZZ, the muscle contracts.
A. stimulating Ca+ release from the SR. B. blocking Ca2+ release from SR C. stimulating action potential formation and/or propagation in the nerve D. stimulating action potential formation and/or propagation in muscle E. blocking action potential propagation in muscle - How would you explain the difference between relaxation of a muscle and inhibition of a muscle? A. Inhibition is a process affecting motor neuron activity, while relaxation is a muscle process without motor neuron input. B. Relaxation is a decrease in myosin activity by phosphorylation, while inhibition is a decrease in ACh release at neuromuscular junction. C. Inhibition is the prevention of Ca2+ release, while relaxation is the removal of Na+ ions. D. Relaxation occurs in motor neurons while inhibition is a muscle event. E. Relaxation is a process using gamma motor neurons while inhibition involves alpha-‐motor neurons.
- Manganese ions block L-‐type calcium channels in the cardiac muscle membrane. How would the presence of sub-‐maximum levels of manganese in the extracellular fluid affect the contraction of heart muscle? A. The heart would beat less forcefully. B. The contraction phase would be prolonged. C. The refractory period would lengthen. D. The heart rate would increase. E. The plateau phase of contraction would be longer.
- When the afferent nerves from all baroreceptors are accidentally cut in an experimental animal, what do you NOT expect to observe? A. a decrease in the diameter of veins B. an increase in stroke volume C. a decreases in heart rate D. an increase in sympathetic nervous system output E. a decrease in diameter of arterioles
Section 3 EXTRA CREDIT. Score on these 3 question are applied to exam one grade.
- In the heart, voltage-gated Na+ channels are found in the ____ cells and contribute to the ____ phase of the action potential. A. contractile; depolarization B. autorhythmic and contractile; repolarization C. autorhythmic and contractile; depolarization D. autorhythmic; depolarization E. contractile; plateau
- While the ACh-‐receptor conducts both Na+ and K+ ions, it is the conductance of [A. Na+/ B. K+] that results in depolarization.
- For a skeletal muscle cell, which one of the following best represents the action potential (solid line), a muscle twitch (dashed line) and the temporal relationship between them?
A. A
B. B
C. C
D. D
E. E
Answer Key for Test “draft ex 2 f22”, 10/13/ No. in Q-‐Bank
No. on Test Correct Answer
14 209 46 E 12 237 47 A 13 79 48 A 14 84 49 A 15 221 50 C 14 294 51 A 12 212 52 A 12 87 53 A
Bio
W
EXAM 2 - 50 Questions
[+ 3 extra credit towards ex 1]
I have submitted my scantron for
grading:
PRINT NAME:
I certify that I have followed the WSU
STUDENT CODE OF CONTENT, and have
not cheated in any shape or form.
(sign your name)
V
- Muscle fatigue A. may involve the degree of ACh release from the motor neuron B. is a non-‐reversible condition C. is only driven by central components D. may involve accumulation of calcium ions around myosin. E. may involve a decrease inactivity of ACh esterase
- The following is a representation of a Wigger's diagram of the cardiac cycle. The solid line is pressure in the left ventricle while the dashed line is pressure in the aorta. Based on this diagram, which of the following statements is FALSE?
A. The ventricle muscle has stopped active contraction near D. B. At B, the ventricle is undergoing isovolumetric contraction. C. Blood begins to flow into the aorta at C. D. The second heart sound is heard at E. E. The AV valves are opening at C.
- Each of the following changes will result in increased blood flow to a tissue EXCEPT: A. decreased peripheral resistance B. increased blood volume C. relaxation of precapillary sphincters D. increased blood pressure E. decreased vessel diameter
- Put these events in the correct chronological sequence:
- Muscle action potentials are initiated.
- Transverse tubules convey potentials into the interior of the cell.
- Myosin dependent contractile cycles begin.
- End plate depolarizes as sodium ions enter.
- Ca2+ is released from the sarcoplasmic reticulum.
- Acetylcholine binds to receptors on the motor end plate.
- Ca2+ ions bind to troponin, pulling on tropomyosin A. 6, 5, 2, 1, 4, 7, 3 B. 3, 6, 1, 5, 7, 2, 4 C. 3, 6, 1, 2, 5, 7, 4 D. 6, 4, 1, 2, 5, 7, 3 E. 4, 5, 1, 7, 2, 6, 3
- The following is a diagram of the NMJ and a muscle depicting aspects of excitation-‐contraction coupling. mn = motor neuron; T-‐t = T-‐tubule; SR =sarcoplasmic reticulum. Based on this diagram, which of the following statements is TRUE?
A. a Ca2+-‐ATPase is located at position 3 B. a mechanically gated calcium release channel is present at 6. C. ligand-‐gated K+ channels are present at position 2. D. voltage-‐gated K+ channels can be found in many places including positions 1, 3 and 7. E. voltage-‐gated Na+ & K+ channels at position 1 are used to propagate a muscle action potentials.
- In the cardiac cycle, leads to , which in turn leads to and therefore. A. depolarization ; change in pressure ; blood flow ; muscle contraction B. contraction; depolarization ; change in pressure ; blood flow C. repolarization ; muscle contraction ; blood flow ; change in pressure D. depolarization ; muscle contraction ; change in pressure ; blood flow E. repolarization ; relaxation ; blood flow ; change in pressure
- A drug G inhibits parasympathetic activity. If administered to an experimental animal, it will do what to the cardiovascular system? A. decrease heart rate B. decrease diameter of arteries C. increase stroke volume D. increase heart rate E. increase diameter of veins
- Which of the following is INCORRECT? A. Autonomic ganglion can be involved in modulating and integrating information. B. Varicosities have the ability to secrete neurotransmitter and allow action potentials to pass through them to the next one. C. All post-‐ganglionic axons end with varicosities. D. The adrenal medulla is a modified parasympathetic ganglion with chromaffin cells secreting hormone into the blood. E. The autonomic nervous system is composed of pre-‐ and post-‐ganglionic neurons,
- Arterioles participate in which of the following functions: A. help regulate mean arterial pressure B. convert the pulsatile nature of arterial blood pressure into a smooth, non-‐ fluctuating pressure in the vessels further downstream C. act as the main determinant of total peripheral resistance D. A and C E. A, B and C
- Thinking about higher order motor control, which of the following is NOT matched correctly? A. cerebellum ; co-‐ordination and timing B. corticospinal tract ; postural reflex control. C. basal ganglion ; motor subroutine planning D. propriceptors ; detection of limb position. E. pre-‐frontal cortex ; planning and decision making
- Which of the following is NOT a property of single-‐unit smooth muscles? A. Their contraction occurs in a coordinated manner. B. Each cell functions independent of its neighbor. C. Electrical responses travel directly between cells. D. Only a proportion of the smooth muscle cells receive autonomic nervous input. E. All smooth muscle cells are connected by gap junctions.
- The following is a diagram of the 1A afferent coming into the dorsal horn of a spinal cord from a muscle spindle (only half of the cord is shown). An interneuron (z) is shown as are two motor neurons (mnA & mnB). Based on the connectivity of this synaptic system
A. mnA will lead to the extrafusal fibers of the same muscle as the 1A afferent B. mnB will lead to the extrafusal fibers of the same muscle as the 1A afferent C. the interneuron Z must be an inhibitory interneuron D. A and C E. B and C
- The flattening of the action potentials of myocardial contractile cells, called the plateau phase, is due to a combination of Ca2+ __________ and K+__________. A. influx, influx B. efflux, efflux C. influx, efflux D. efflux, influx E. none of the above
- In order for blood to enter the heart, A. the atria must be in diastole. B. the pressure in the atria must be lower than in the veins. C. the AV valves must be closed. D. A and B E. A, B and C
- When a skeletal muscle cell contracts and the muscle shortens, A. the actin molecule swivels during the power stroke. B. myosin heads generate a single power stroke. C. the actin ATPase allows the actin molecule to swivel. D. some myosin heads are forming crossbridges as others are releasing them. E. the position of an actin molecule relative to a myosin molecule does not change.
- Which of the following is FALSE? A. Valves are characteristic of both veins and lymphatic vessels and ensure one-‐ way flow. B. Smooth muscle within the walls of veins are important for regulating venous return. C. In the capillary beds of most tissues, there is a net absorption. D. Veins are often referred to as the reservoir vessels of the vascular system. E. Meta-‐arterioles often act as bypass channels within capillary beds.
- In skeletal muscle, the speed with which force is developed is determined by this protein , while relaxation is the role of this protein. A. Ryn-‐R ; Ca2+-‐ATPase B. Myosin ATPase ; Ca2+-‐ATPase C. Ryn-‐R ; Na+-‐Ca2+ exchanger D. DHP-‐R ; Na+-‐Ca2+ exchanger E. Ca2+ ATPase ; DHP-‐Receptor
- All of the following tend to increase as a result of the action of the skeletal muscle pump EXCEPT A. end diastolic volume B. cardiac output C. stroke volume D. venous pooling E. venous return
- If there is no blood flow from A to B, then the pressure in A is _______ the pressure in B. A. equal to B. higher than C. lower than D. Cannot tell from information given
