Download Chapter 7: The Muscular System

Chapter 7: The Muscular System
1.
A)
B)
C)
D)
Ans:
Which surrounds a fascicle?
endomysium
epimysium
fascia
perimysium
D
2.
A)
B)
C)
D)
Ans:
Myofibrils
are located in muscle fibers.
are contractile units.
have striations.
are described by all of these characteristics.
D
3.
A)
B)
C)
D)
Ans:
Myosin is
a protein.
the thin filament.
pulled inward during contraction.
described by all of these characteristics.
A
4.
A)
B)
C)
D)
Ans:
Lactic acid buildup
occurs after strenuous activity.
occurs due to lack of oxygen.
causes cramps.
is described by all of these characteristics.
D
5.
A)
B)
C)
Ans:
Which obeys the all-or-none law?
the whole muscle
a muscle fiber
the whole muscle and a muscle fiber
B
6.
A)
B)
C)
Ans:
Which is on the stationary bone?
insertion
prime mover
origin
C
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7.
A)
B)
C)
Ans:
Fatigue is
receiving many impulses in rapid succession.
the period between stimulation and contraction.
the depletion of ATP.
C
8.
A)
B)
C)
Ans:
Summation is
receiving many impulses in rapid succession.
the period between stimulation and contraction.
the depletion of ATP.
A
9.
A)
B)
C)
Ans:
Latent period is
receiving many impulses in rapid succession.
the period between stimulation and contraction.
the depletion of ATP.
B
10.
A)
B)
C)
D)
Ans:
Adduction is
movement of body part toward midline.
decreasing the joint angle.
movement around an axis.
circumduction.
A
11.
A)
B)
C)
D)
Ans:
Rotation is
movement of body part toward midline.
decreasing the joint angle.
movement around an axis.
circumduction.
C
12.
A)
B)
C)
D)
Ans:
Flexion is
movement of body part toward midline.
decreasing the joint angle.
movement around an axis.
circumduction.
B
13.
A)
B)
C)
D)
Ans:
Movement in a wide circle is
movement of body part toward midline.
decreasing the joint angle.
movement around an axis.
circumduction.
D
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figure 7.1
14. Which letter in figure 7.1 points to the origin?
Ans: a
15. Which letter in figure 7.1 points to the insertion?
Ans: b
16.
A)
B)
C)
Ans:
The biceps and triceps in figure 7.1
are antagonistic.
are synergistic.
depend upon activity to determine antagonism or synergism.
A
17.
A)
B)
C)
Ans:
During which type of contraction does movement occur?
isometric
isotonic
isometric and isotonic
B
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figure 7.2
18. Which letter in figure 7.2 points to the masseter?
Ans: b
19. Which letter in figure 7.2 points to the pectoralis major?
Ans: a
20. Which letter in figure 7.2 points to the sartorius?
Ans: d
21. Which letter in figure 7.2 points to the gastrocnemius?
Ans: c
figure 7.3
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22. Which letter in figure 7.3 points to the latissimus dorsi?
Ans: d
23. Which letter in figure 7.3 points to the trapezius?
Ans: b
24. Which letter in figure 7.3 points to the external oblique?
Ans: a
25. Which letter in figure 7.3 points to the deltoid?
Ans: c
figure 7.4
26. Which letter in figure 7.4 points to the rectus abdominus?
Ans: a
27. Which letter in figure 7.4 points to the sternocleidomastoid?
Ans: d
28. Which letter in figure 7.4 points to the internal oblique?
Ans: c
29.
A)
B)
C)
D)
Ans:
The __________ raises your eyebrow.
biceps brachii
frontalis
hamstring group
gluteus maximus
B
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30.
A)
B)
C)
D)
Ans:
The __________ extends your thigh.
biceps brachii
frontalis
hamstring group
gluteus maximus
D
31.
A)
B)
C)
D)
Ans:
The __________ flexes your elbow.
biceps brachii
frontalis
hamstring group
gluteus maximus
A
32.
A)
B)
C)
D)
Ans:
The __________ flexes your leg.
biceps brachii
frontalis
hamstring group
gluteus maximus
C
33. What are the sources of ATP for muscle contraction?
Ans: 1. Produced in the mitochondria via aerobic cellular respiration. 2. Regenerated by
creatine phosphate. 3. Produced via anaerobic respiration.
34. What is the reason for lactic acid buildup and how is it removed?
Ans: Lactic acid is an end product of anaerobic respiration. It is removed by deep breathing
following exercise, which supplies the oxygen required to metabolize the lactic acid.
35. What effect does lack of exercise have on muscle tissue?
Ans: Forceful contractions of muscles cause them to increase in size while lack of
contractions or weak contractions cause them to decrease in size.
36. Muscle fatigue is usually due to lactic acid accumulation in the muscles. How and why
does this happen?
Ans: When muscle fibers fatigue, they have run out of ATP. Lactic acid builds up as a result
of anaerobic respiration and produces muscle aching and fatigue.
37. When chewing a piece of gum, what muscles would you use?
Ans: The masseter and temporalis muscles mainly. The buccinator muscle would help hold
the gum in contact with the teeth.
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38. Distinguish between epimysium, perimysium, and endomysium.
Ans: Epimysium - connective tissue covering an entire muscle (fascia)
Perimysium - connective tissue surrounding fascicles (bundles of muscle fibers within a
muscle)
Endomysium - connective tissue surrounding individual muscle fibers (cells) within a
fascicle
39. What is meant by oxygen debt?
Ans: When there is insufficient oxygen available to generate ATP aerobically, anaerobic
respiration will commence. Lactic acid is a product of anaerobic respiration that causes
muscle fatigue and pain. Following strenuous exercise we must continue to breathe
deeply in order to supply the oxygen required to metabolize the lactic acid that has built
up in our cells. This oxygen represents an oxygen debt that must be repaid following
anaerobic respiration.
40. If muscle fibers obey the all-or-none law, then how can muscles exhibit various
strengths of contraction?
Ans: Muscles can exhibit various strengths of contraction because different numbers of fibers
can be contracting during muscle contraction. When more muscle fibers are contracting
the whole-muscle contraction is of greater strength. When few muscle fibers are
contracting the whole-muscle contraction is of lesser strength.
41. List and discuss benefits of exercise.
Ans: See Medical Focus in text.
42. Arrange the following terms in order from smallest to largest: fascicle, muscle, muscle
fiber, myofibril, myofilament.
Ans: myofilament, myofibril, muscle fiber, fascicle, muscle.
43. Give one example each for isometric and isotonic contraction.
Ans: Answers may vary, but isometric contraction will not result in the shortening of a
muscle while isotonic contraction will.
44. List, in order, the three components of a single muscle twitch.
Ans: Latent period, contraction period, relaxation period.
45. Describe the relationship between summation and tetanus.
Ans: When a muscle receives numerous stimuli in succession, the force of the muscle
contraction will increase until it reaches a maximum level. The maximal sustained
contraction that occurs is called tetanus.
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46.
A)
B)
C)
D)
Ans:
Which muscle tissue type has intercalated disks?
cardiac
skeletal
smooth
Both cardiac and skeletal are correct.
A
47.
A)
B)
C)
D)
Ans:
Which muscle tissue type is striated?
cardiac
skeletal
smooth
Both cardiac and skeletal are correct.
D
48.
A)
B)
C)
D)
Ans:
A sarcomere is
formed from myosin only.
the distance between Z lines.
the length of the H zone.
between the I bands.
B
49.
A)
B)
C)
D)
Ans:
What does calcium do during muscle contraction?
binds to troponin
binds to the crossbridges
supplies energy
hydrolyzes ATP
A
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