 |
1 |  |  During contraction, muscles shorten __________ , and lengthen __________ . |
|  | A) | forcefully, forcefully |
|  | B) | forcefully, passively |
|  | C) | passively, forcefully |
|  | D) | passively, passively |
 |
 |
2 |  |  Muscle cells that are cylindrical and branched, each with a single, centrally located nucleus, and that contract spontaneously are |
|  | A) | cardiac muscle. |
|  | B) | skeletal muscle. |
|  | C) | smooth muscle. |
|  | D) | unknown: not enough characteristics to determine the type of muscle |
 |
 |
3 |  |  __________ surrounds each muscle fasciculus, whereas __________ surrounds each muscle fiber. |
|  | A) | Epimysium, perimysium |
|  | B) | Perimysium, endomysium |
|  | C) | Epimysium, endomysium |
|  | D) | Endomysium, perimysium |
|  | E) | Endomysium, epimysium |
 |
 |
4 |  |  Which of these layers of a skeletal muscle is the same as the fascia? |
|  | A) | sarcolemma |
|  | B) | perimysium |
|  | C) | fasciculus (bundle) |
|  | D) | epimysium |
|  | E) | endomysium |
 |
 |
5 |  |  Each muscle cell is a |
|  | A) | fasciculus. |
|  | B) | sarcomere. |
|  | C) | fiber. |
|  | D) | myofibril. |
|  | E) | myofilament. |
 |
 |
6 |  |  Most of the interior of muscle fibers is filled with |
|  | A) | fasciculi. |
|  | B) | myofibrils. |
|  | C) | nuclei. |
|  | D) | sarcoplasm. |
|  | E) | sarcoplasmic reticulum. |
 |
 |
7 |  |  Which of these is NOT a part of the actin myofilament? |
|  | A) | actin |
|  | B) | cisternae |
|  | C) | tropomyosin |
|  | D) | troponin |
 |
 |
8 |  |  Which of these locations has the ability to break down ATP, which releases energy? |
|  | A) | globular actin molecule |
|  | B) | head of myosin molecule |
|  | C) | troponin molecule |
|  | D) | tropomyosin molecule |
|  | E) | troponin-tropomyosin complex |
 |
 |
9 |  |  Troponin binds to |
|  | A) | actin. |
|  | B) | calcium ions. |
|  | C) | tropomyosin. |
|  | D) | all of these |
 |
 |
10 |  |  Which of these units contains overlapping actin and myosin myofilaments? |
|  | A) | A band |
|  | B) | H zone |
|  | C) | I band |
|  | D) | M line |
|  | E) | Z disk |
 |
 |
11 |  |  Which of these units contains the Z disk? |
|  | A) | A band |
|  | B) | H zone |
|  | C) | I band |
|  | D) | M line |
 |
 |
12 |  |  Which of these regions shorten(s) during skeletal muscle contraction? |
|  | A) | A band |
|  | B) | I band |
|  | C) | H zone |
|  | D) | both a and b |
|  | E) | both b and c |
 |
 |
13 |  |  The resting membrane potential occurs when |
|  | A) | sodium ions diffuse into the cell. |
|  | B) | sodium ions diffuse out of the cell. |
|  | C) | potassium ions diffuse into the cell. |
|  | D) | potassium ions diffuse out of the cell. |
|  | E) | large negative molecules diffuse out of the cell. |
 |
 |
14 |  |  If the permeability of the plasma membrane to Na+ ions increases, the result is |
|  | A) | depolarization of the plasma membrane. |
|  | B) | repolarization of the plasma membrane. |
|  | C) | little, if any, change in the resting membrane potential of the plasma membrane. |
 |
 |
15 |  |  In the neuromuscular junction, the axon is also called the |
|  | A) | postsynaptic membrane. |
|  | B) | presynaptic terminal. |
|  | C) | synaptic cleft. |
|  | D) | synaptic vesicle. |
 |
 |
16 |  |  Given these events:
1. acetylcholine is released from synaptic vesicles 2. an action potential reaches the presynaptic terminal 3. Ca2+ ions diffuse into the cell 4. acetylcholine is secreted from the presynaptic terminal by exocytosis
Choose the arrangement that lists the events in the order they occur when an action potential travels through the axon of a motor neuron. |
|  | A) | 1,2,3,4 |
|  | B) | 1,3,4,2 |
|  | C) | 2,1,3,4 |
|  | D) | 2,3,1,4 |
|  | E) | 3,2,1,4 |
 |
 |
17 |  |  Given these events:
1. acetylcholine binds to receptors on the postsynaptic membrane 2. acetylcholinesterase breaks down acetylcholine 3. choline is reabsorbed by presynaptic membrane 4. depolarization of postsynaptic membrane occurs 5. ligand-gated Na+ ion channels open
Choose the arrangement that lists the events in the order they occur when an action potential travels through the axon of a motor neuron. |
|  | A) | 1,2,3,4,5 |
|  | B) | 1,5,4,2,3 |
|  | C) | 2,1,3,4,5 |
|  | D) | 4,3,2,1,5 |
|  | E) | 5,4,1,2,3 |
 |
 |
18 |  |  The drug atropine blocks neurotransmitter receptors on the postsynaptic terminal of the neuromuscular junction. This causes |
|  | A) | flaccid paralysis. |
|  | B) | spastic paralysis. |
|  | C) | no change in muscle function. |
 |
 |
19 |  |  The enlarged areas of the sarcoplasmic reticulum near the T tubules are the |
|  | A) | sarcolemma. |
|  | B) | sarcomeres. |
|  | C) | terminal cisternae. |
|  | D) | troponin molecules. |
|  | E) | tropomyosin molecules. |
 |
 |
20 |  |  Given these events:
1. action potential travels along the sarcolemma 2. T tubules undergo depolarization 3. voltage-gated Ca2+ ion channels in sarcoplasmic reticulum open 4. Ca2+ ions diffuse into the sarcoplasm 5. Ca2+ ions bind to troponin molecules
Choose the arrangement that lists these events in the order they occur following a single stimulation of a skeletal muscle cell. |
|  | A) | 1,2,3,4,5 |
|  | B) | 1,3,5,4,2 |
|  | C) | 2,1,3,4,5 |
|  | D) | 3,1,5,2,4 |
|  | E) | 4,5,12,3 |
 |
 |
21 |  |  During muscle contraction, which of these processes requires ATP? |
|  | A) | transport of calcium ions into the sarcoplasmic reticulum |
|  | B) | release of cross-bridges |
|  | C) | formation of cross-bridges |
|  | D) | active transport of Na+ and K+ ions |
|  | E) | all of these |
 |
 |
22 |  |  Cross bridges form during muscle contraction when myosin comes in contact with active sites on |
|  | A) | troponin molecules. |
|  | B) | tropomyosin molecules. |
|  | C) | calcium ions. |
|  | D) | acetylcholine molecules. |
|  | E) | actin molecules. |
 |
 |
23 |  |  Given these events:
1. active sites on actin myofilament are exposed 2. actin myofilament slides over myosin myofilament 3. Ca2+ ion binds to troponin 4. myosin heads move 5. cross bridges form
Choose the arrangement that lists the correct order in which they occurduring a single stimulation of a skeletal muscle. |
|  | A) | 4,3,2,1,5 |
|  | B) | 3,1,5,4,2 |
|  | C) | 3,2,5,4,1 |
|  | D) | 2,4,3,5,1 |
|  | E) | 1,2,3,4,5 |
 |
 |
24 |  |  For cross bridge release, it is necessary for __________ to attach to the myosin head. |
|  | A) | a tropomyosin molecule |
|  | B) | ATP |
|  | C) | Ca2+ ions |
|  | D) | a troponin molecule |
|  | E) | the sarcolemma |
 |
 |
25 |  |  Which of these is (are) required for the relaxation of a muscle fiber? |
|  | A) | ATP |
|  | B) | Ca2+ ion uptake into the sarcoplasmic reticulum |
|  | C) | acetylcholinesterase activity |
|  | D) | no additional stimulation of the neuron |
|  | E) | all of these |
 |
 |
26 |  |  A motor unit is |
|  | A) | all the fibers in one muscle. |
|  | B) | all the fibers in one fasciculus. |
|  | C) | all the muscle fibers innervated by a single motor neuron. |
|  | D) | all the nerves that innervate one muscle fiber. |
 |
 |
27 |  |  Even though each muscle fiber responds in all-or-none fashion, a whole muscle can contract with varying force because of |
|  | A) | different threshold values of each fiber. |
|  | B) | total tetanus of the muscle. |
|  | C) | multiple motor unit summation. |
|  | D) | rigor mortis. |
|  | E) | the lag phase of contraction. |
 |
 |
28 |  |  Multiple-wave summation is caused by |
|  | A) | stimuli of increasing size. |
|  | B) | increasing number of nerves stimulated. |
|  | C) | increasing frequency of stimuli. |
|  | D) | complete relaxation between stimuli. |
|  | E) | a subthreshold stimulus. |
 |
 |
29 |  |  Which of these processes results in an increase in the force of contraction of a whole muscle? |
|  | A) | multiple motor unit summation |
|  | B) | multiple wave summation |
|  | C) | treppe |
|  | D) | all of these |
 |
 |
30 |  |  Unlike neurons, muscle fibers have no |
|  | A) | absolute refractory period. |
|  | B) | action potentials. |
|  | C) | resting membrane potential. |
|  | D) | cell membrane. |
|  | E) | mitochondria. |
 |
 |
31 |  |  A muscle contraction in which the muscle produces an increasing tension, but the length remains constant is a(n) |
|  | A) | isometric contraction. |
|  | B) | isotonic contraction. |
|  | C) | concentric contraction. |
|  | D) | eccentric contraction. |
 |
 |
32 |  |  The most common type of fatigue is: |
|  | A) | muscular fatigue. |
|  | B) | psychological fatigue. |
|  | C) | synaptic fatigue. |
|  | D) | sarcoplasmic reticulum fatigue. |
|  | E) | army fatigue. |
 |
 |
33 |  |  Anaerobic respiration |
|  | A) | produces 38 ATPs per glucose molecule. |
|  | B) | produces an oxygen debt. |
|  | C) | occurs in resting muscles or muscles undergoing long-term exercise. |
|  | D) | can use fatty acid to produce ATP. |
|  | E) | all of these |
 |
 |
34 |  |  Given these sources of energy during exercise: 1. anaerobic respiration 2. aerobic respiration 3. ATP and creatine phosphate in the cell The correct sequence for the use of these energy sources by muscle cells when an individual starts exercising is |
|  | A) | 1,2,3. |
|  | B) | 1,3,2. |
|  | C) | 2,1,3. |
|  | D) | 3,2,1. |
|  | E) | 3,1,2. |
 |
 |
35 |  |  Fatty acids can be used as an energy source for muscle contraction during |
|  | A) | aerobic exercise. |
|  | B) | fast, intense exercise. |
|  | C) | anaerobic respiration. |
|  | D) | breakdown of glycogen to glucose. |
|  | E) | the time of oxygen debt. |
 |
 |
36 |  |  Fast-twitch muscle fibers |
|  | A) | are more resistant to fatigue than slow-twitch fibers. |
|  | B) | have a richer blood supply than slow-twitch fibers. |
|  | C) | have a larger amount of stored glycogen than slow-twitch fibers. |
|  | D) | have more mitochondria than slow-twitch fibers. |
|  | E) | have more myoglobin than slow-twitch fibers. |
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37 |  |  Which of these characteristics is typical of a slow-twitch muscle fiber? |
|  | A) | large number of mitochondria |
|  | B) | few capillaries |
|  | C) | low myoglobin content |
|  | D) | largely anaerobic |
|  | E) | b, c, and d |
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38 |  |  Which of these is part of the contraction process of smooth muscle? |
|  | A) | Calcium ions bind to troponin. |
|  | B) | Caveolae bind with calcium to produce cross bridges. |
|  | C) | Troponin and tropomyosin are moved. |
|  | D) | Calcium ions bind to calmodulin, which activates an enzyme. |
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39 |  |  Which of these is correctly matched? |
|  | A) | multiunit smooth muscle -- spontaneous contractions |
|  | B) | visceral smooth muscle -- contracts when stretched |
|  | C) | skeletal muscle -- slower, longer lasting contractions than smooth muscle |
|  | D) | multiunit smooth muscle -- numerous gap junctions; autorhythmic |
|  | E) | all of these |
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40 |  |  Visceral smooth muscle |
|  | A) | responds in an all-or-none fashion to action potentials. |
|  | B) | has slow waves of depolarization and repolarization. |
|  | C) | has depolarization occur when the cell becomes more permeable to Na+ ions and K+ ions. |
|  | D) | requires a stimulus from a neuron or hormone. |
|  | E) | produces strong contractions that only last for a few milliseconds. |
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