1. The connective tissue layer that surrounds individual muscle fibers is called
a. endomysium b. epimysium c. perimysium
d. sarcomere e. tendon
2. The structural and functional repeating unit of a muscle fiber is called
a. sarcolemma b. sarcomere c. fascicle
d. myofilament e. sarcoplasmic reticulum
3. Thick filaments mostly contain
a. actin b. myosin c. troponin
d. tropomyosin e. collagen
4. Which one of the following stores calcium in the myofiber?
a. sarcolemma b. sarcomere c. T -tubule
d. myofilament e. sarcoplasmic reticulum
5. Action potentials are propagated from the surface to the interior of a muscle fiber by way of
a. the sarcomeres b. the sarcoplasmic reticulum c. the endomysium
d. the myofibrils e. the transverse tubules (T tubules)
6. Arrange the following steps in their correct sequence for contraction process:
1. Calcium is released
2. Myosin of thick filament binds with actin of thin filaments
3. Action potential travels down the sarcolemma and transverse tubules (T tubules)
4. Action potential travels down an axon
5. Calcium binds to a protein in the the thin filament
6. Thick and thin filaments slide over each other
a. 4, 6, 3, 2, 5, 1 b. 4, 3, 2, 1, 6, 5 c. 4, 3, 1, 5, 2, 6
d. 4, 3, 1, 6, 2, 5 e. 1, 2, 3, 4, 5, 6
7. The neurotransmitter released at the neuromuscular junction in skeletal muscle is
a. acetylcholineesterase b. serotonin c. acetylcholine
d. calcium e. dopamine
8. The protein that binds calcium ions in skeletal muscle is
a. tropomyosin b. myosin c. troponin d. actin e. titin
9. During anaerobic glycolysis in muscle cells
a. ATP is produced. b. lactic acid is produced. c. oxygen is not consumed.
d. glucose is broken down. e. All of the answers are correct.
10. Which structure in a sarcomere gets larger during muscle contraction?
a. I band
b. H band
c. Z line
d. Zone of overlap
e. M line
11. Your friend is a competitive cyclist and is taking anabolic steroids. How will these affect his skeletal muscles?
a. It would stimulate atrophy
b. It would stimulate hypertrophy
c. It would stimulate energy use and heat production.
d. It would decrease heat production by muscle tissue.
e. It would cause aerobic metabolism to shut down
- In a relaxed muscle fiber, the active sites of actin are blocked by
- a. tropomyosin b. troponin c. calcium ions
- d. myosin heads e. elastic filaments
- You are working out with weights and after a while you notice that your muscles are becoming larger. This can be best explained due to
- a. increase in skeletal muscle cells due to cell division
- b. skeletal muscle hypertrophy
- c. increase in skeletal muscle cells due mitosis
- d. skeletal muscle hyperplasia
- e. skeletal muscle atrophy
14. Muscles that guard entrances and exits of internal passageways are ________ muscles.
15. A muscle that assists the muscle that is primarily responsible for a given action is a(n)
16. Muscles with fibers that run at an angle to the longitudinal axis of the body are called
17. Jill suffers a severe cut that severs the tendon that attaches the insertion of the brachialis. As a result of this injury, what action is likely more difficult for her to perform?
a. flex her forearm
b. extend her forearm
d. flex and adduct her hand
e. flex her shoulder
18. The "kissing muscle" that purses the lips and closes the mouth is the
b. orbicularis oris.
d. orbicularis oculi.
22. Which of the following is not an extrinsic eye muscle?
a. lateral rectus
b. superior oblique
c. external oblique
d. medial rectus
e. inferior rectus
23. From its name, you can tell that the sternocleidomastoid inserts on the
c. mastoid process.
24. All of the following muscles are superficial EXCEPT
a. latissimus dorsi b. transversus abdominis c. trapezius
d. pectoralis major e. biceps brachii
25. Mary looked down at her bright new shiny shoes. She was engaging her ________ muscle.
a. medial rectus
b. inferior rectus
c. inferior oblique
d. superior rectus
e. lateral rectus
26. During abdominal surgery, the surgeon makes a cut lateral and parallel to the linea alba. The muscle that would be cut is the
a. internal oblique.
c. external abdominal oblique.
d. transversus abdominis.
e. rectus abdominis.
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