CHAPTER 43—MUSCLES, BONES, AND BODY MOVEMENTS
MULTIPLE CHOICE
1. About how long is required for a Mexican leaf frog to capture a cricket, from the beginning of
movement by the frog to the closing of the frog’s mouth?
a.
50 milliseconds
b.
1 second
c.
80 milliseconds
d.
260 milliseconds
e.
3 seconds
2. Which muscle type is found in the walls of body tubes and cavities of vertebrates, such as blood
vessels and the intestines?
a.
cardiac
b.
smooth
c.
skeletal
d.
rough
e.
epithelial
3. Skeletal muscle cells have ____ and are controlled by ____.
a.
many nuclei; the somatic nervous system
b.
many nuclei; the autonomic nervous system
c.
one nucleus each; the autonomic nervous system
d.
one nucleus each; the somatic nervous system
e.
two nuclei each; the somatic nervous system
4. A typical human body has ____ skeletal muscles.
a.
78
b.
168
c.
206
d.
417
e.
over 600
5. Skeletal muscles are connected to bones by cords of connective tissue called
a.
muscle fibers.
b.
sarcomeres.
c.
tendons.
d.
ligaments.
e.
myofibrils.
6. Skeletal muscles are made up of bundles of elongated, cylindrical cells called
a.
muscle fibers.
b.
sarcomeres.
c.
tendons.
d.
ligaments.
e.
myofibrils.
7. Individual skeletal muscle cells are packed with cylindrical contractile elements about 1 mm in
diameter called
a.
muscle fibers.
b.
sarcomeres.
c.
tendons.
d.
ligaments.
e.
myofibrils.
8. Thick filaments are parallel bundles of ____ molecules.
a.
actin
b.
tropomyosin
c.
acetylcholine
d.
myosin
e.
troponin
9. “A bands” in skeletal muscle are composed of
a.
discs to which thin filaments are anchored.
b.
stacked thick filaments along with parts of thin filaments that overlap both ends.
c.
thin filaments but no thick filaments.
d.
thick filaments but no thin filaments.
e.
discs to which thick filaments are anchored.
10. “H zones” in skeletal muscle are composed of
a.
discs to which thin filaments are anchored.
b.
stacked thick filaments along with parts of thin filaments that overlap both ends.
c.
thin filaments but no thick filaments.
d.
thick filaments but no thin filaments.
e.
discs to which thick filaments are anchored.
11. “Z lines” in skeletal muscle are composed of
a.
discs to which thin filaments are anchored.
b.
stacked thick filaments along with parts of thin filaments that overlap both ends.
c.
thin filaments but no thick filaments.
d.
thick filaments but no thin filaments.
e.
discs to which thick filaments are anchored.
12. “I bands” in skeletal muscle are composed of
a.
discs to which thin filaments are anchored.
b.
stacked thick filaments along with parts of thin filaments that overlap both ends.
c.
thin filaments but no thick filaments.
d.
thick filaments but no thin filaments.
e.
discs to which thick filaments are anchored.
13. The region between two adjacent Z lines is a
a.
muscle fiber.
b.
sarcomere.
c.
tendon.
d.
ligament.
e.
myofibril.
14. The ____ is a system of vesicles that wraps around each A band and I band and stores ions that are
used in muscle contractions.
a.
neuromuscular junction
b.
Golgi apparatus
c.
endolemma
d.
microvillus
e.
sarcoplasmic reticulum
15. In skeletal muscle contraction, which of the following acts to allow the crossbridge cycle to occur
when it flows into the cytosol through open ion channels?
a.
troponin
b.
Ca2+
c.
tropomyosin
d.
ATP
e.
acetylcholine
16. In skeletal muscle contraction, which of the following is the neurotransmitter released at the axon
terminal to trigger an action potential in the muscle cell?
a.
troponin
b.
Ca2+
c.
tropomyosin
d.
ATP
e.
acetylcholine
17. In skeletal muscle contraction, which of the following must be moved to the grooves in the actin
double helix to uncover the crossbridge binding site?
a.
troponin
b.
Ca2+
c.
tropomyosin
d.
ATP
e.
acetylcholine
18. In skeletal muscle contraction, which of the following undergoes a conformational change when it
binds to a specific ion and then uncovers the crossbridge binding site by causing another factor to be
moved to the grooves in the actin double helix?
a.
troponin
b.
Ca2+
c.
tropomyosin
d.
ATP
e.
acetylcholine
19. In skeletal muscle contraction, which of the following binds to myosin?
a.
troponin
b.
Ca2+
c.
tropomyosin
d.
ATP
e.
acetylcholine
20. What action causes the shape change in the myosin crossbridge that directly triggers the power stroke
in skeletal muscle contraction?
a.
binding of myosin to actin
b.
binding of tropomyosin to myosin
c.
binding of myosin to troponin
d.
binding of tropomyosin to actin
e.
binding of troponin to tropomyosin
21. Duchenne muscular dystrophy is caused by
a.
a mutation that weakens the cytoskeleton of the muscle fiber.
b.
a mutation that weakens myofibrils.
c.
a mutation in the X and Y chromosome.
d.
a mutation that disrupts the sarcomere.
e.
a mutation that increases the transmission of force.
22. A defect in transport of which ion would have the most direct effect on muscle contraction?
a.
Cl−
b.
K+
c.
Ca2+
d.
Na+
e.
Zn2+
23. Clostridium botulinum produces a deadly toxin that stops muscle contractions by
a.
destroying cell membranes.
b.
killing mitochondria.
c.
disrupting the structure of actin filaments.
d.
preventing ATP synthesis.
e.
blocking acetylcholine release.
24. The frozen contraction of muscle cells called rigor mortis occurs because after death
a.
ions are not available in muscle cells.
b.
tropomyosin breaks down quickly.
c.
neurotransmitters are no longer released.
d.
ATP production stops.
e.
muscle cells are flooded with neurotransmitters.
25. A single, weak contraction of a muscle fiber is called
a.
an action potential.
b.
a muscle twitch.
c.
fatigue.
d.
tetanus.
e.
constriction.
26. A muscle contraction where fibers cannot relax at all between stimuli is called
a.
an action potential.
b.
a muscle twitch.
c.
fatigue.
d.
tetanus.
e.
constriction.
27. Myoglobin content is high in
a.
fast anaerobic fibers.
b.
fast aerobic and fast anaerobic muscle fibers.
c.
slow muscle fibers and fast aerobic muscle fibers.
d.
slow muscle fibers.
e.
fast aerobic fibers.
28. A rapid, powerful movement of short duration that could not be sustained for long would likely
involve mainly
a.
fast anaerobic fibers.
b.
fast aerobic and fast anaerobic muscle fibers.
c.
slow muscle fibers and fast aerobic muscle fibers.
d.
slow muscle fibers.
e.
fast aerobic fibers.
29. The main role of myoglobin in muscle fibers is to
a.
magnify responses to neurotransmitters.
b.
sequester ions.
c.
synthesize ATP.
d.
store oxygen.
e.
enhance the strength of the power stroke.
30. Unlike endurance training, weight lifting will
a.
convert slow muscle fibers to fast muscle fibers.
b.
convert fast muscle fibers to slow muscle fibers.
c.
convert fast muscle fibers from the anaerobic to the aerobic type.
d.
convert fast muscle fibers from the aerobic to the anaerobic type.
e.
convert fat to muscle fibers.
31. A motor unit is
a.
a single muscle fiber activated by one neuron.
b.
the complete set of muscle fibers in a single muscle.
c.
a single sarcomere.
d.
a single muscle fiber activated by many neurons.
e.
a group of muscle fibers activated by one neuron.
32. By _____, researchers had established the location and arrangement of actin and myosin in _______
muscle.
a.
1924; striated
b.
1954; striated
c.
1924; smooth
d.
1994; smooth
e.
1904; smooth
33. The mechanism of muscle contraction was first studied using
a.
striated muscle examined using high-resolution light microscopy.
b.
smooth muscle examined using high-resolution light microscopy.
c.
striated muscle examined using high-resolution electron microscopy.
d.
smooth muscle examined using high-resolution electron microscopy.
e.
cardiac muscle examine using high-resolution electron microscopy
34. High-intensity training in racehorses results in
a.
muscle atrophy.
d.
no change in the expression of genes, but
changes in phenotypes.
b.
the expression of genes in metabolism,
oxidative phosphorylation, and muscle
structure.
e.
changes in the expression of genes, but no
changes in phenotypes.
c.
no phenotypic or biochemical changes
35. Tube feet of sea stars, erectile tissue of the penis in vertebrates, and the bodies of cnidarians are all
supported by
a.
an exoskeleton.
b.
only nonskeletal structures.
c.
a hydrostatic skeleton.
d.
an endoskeleton.
e.
joined exo- and endoskeletons.
36. The bodies of arthropods are supported mainly by
a.
an exoskeleton.
b.
only nonskeletal structures.
c.
a hydrostatic skeleton.
d.
an endoskeleton.
e.
joined exo- and endoskeletons.
37. For humans and most vertebrates the body is supported primarily by
a.
an exoskeleton.
b.
only nonskeletal structures.
c.
a hydrostatic skeleton.
d.
an endoskeleton.
e.
joined exo- and endoskeletons.
38. A typical human body has ____ bones.
a.
78
b.
168
c.
206
d.
417
e.
over 600
39. The ribs and sternum are considered to be part of
a.
both the axial skeleton and the appendicular skeleton.
b.
the axial skeleton.
c.
neither the axial skeleton nor the appendicular skeleton.
d.
the appendicular skeleton.
e.
the adaxial skeleton
40. The radius and ulna are considered to be part of
a.
both the axial skeleton and the appendicular skeleton.
b.
the axial skeleton.
c.
neither the axial skeleton nor the appendicular skeleton.
d.
the appendicular skeleton.
e.
the adaxial skeleton
41. Bones are organs with more than one tissue type present. Which of the following is NOT found as part
of any bones?
a.
blood vessels
b.
bone tissue
c.
adipose tissue
d.
nerves
e.
brown marrow
42. The primary source of new red blood cells in mammals is the
a.
liver.
b.
blood, itself.
c.
spleen.
d.
heart.
e.
bone marrow.
43. Bone plays a critical role in providing ____ for the blood.
a.
sodium and calcium ions
b.
magnesium and phosphate ions
c.
carbon dioxide
d.
phosphate and calcium ions
e.
calcium ions and oxygen
44. These joints are somewhat moveable, but they do not have a fluid-filled capsule surrounding them.
They have fibrous connective tissue covering the ends of the bones involved.
a.
synovial joints
b.
cartilaginous joints
c.
fibrous joints
d.
non-fibrous joints
e.
antagonistic joints
45. These joints have bones joined by stiff fibers of connective tissue and are essentially immobile.
a.
synovial joints
b.
cartilaginous joints
c.
fibrous joints
d.
non-synovial joints
e.
non-fibrous joints
46. These joints are usually highly moveable. They have a fluid-filled capsule of connective tissue
surrounding them.
a.
synovial joints
b.
cartilaginous joints
c.
fibrous joints
d.
non-synovial joints
e.
non-fibrous joints
47. Synovial joints are held together by
a.
muscle fibers.
b.
sarcomeres.
c.
tendons.
d.
ligaments.
e.
myofibrils.
48. The human elbow is an example of which kind of joint?
a.
synovial joint
b.
cartilaginous joint
c.
fibrous joint
d.
non-fibrous joint
e.
non-synovial joint
49. Cranial bones are held together by which kind of joint?
a.
synovial joint
b.
cartilaginous joint
c.
fibrous joint
d.
non-synovial joint
e.
antagonistic joint
50. Human vertebrae are held together by which kind of joint?
a.
synovial joint
b.
cartilaginous joint
c.
fibrous joint
d.
both fibrous and cartilaginous joints
e.
both synovial and fibrous joints
51. A muscle that causes any type of movement in a joint when it contracts is called a(n)
a.
flexor.
b.
agonist.
c.
depressor.
d.
antagonist.
e.
extensor.
52. A muscle that increases the angle between two bones at a joint is called a(n)
a.
flexor.
b.
agonist.
c.
depressor.
d.
antagonist.
e.
extensor.
53. A muscle that decreases the angle between two bones at a joint is called a(n)
a.
flexor.
b.
agonist.
c.
depressor.
d.
antagonist.
e.
extensor.
54. A muscle that has the opposite effect to that of another muscle at the same joint is called a(n)
a.
flexor.
b.
agonist.
c.
depressor.
d.
antagonist.
e.
extensor.
55. Which of the following is an example of an antagonist muscle pair in humans?
a.
calf and gluteus maximus
b.
deltoid and pectoral
c.
hamstring and biceps
d.
calf and hamstring
e.
biceps and triceps
56. Skeletal muscle growth and development is inhibited by ____ produced in muscle cells.
a.
erythropoietin
b.
acetylcholine
c.
epidermal growth factor
d.
epinephrine
e.
myostatin
57. Which of the following is thought to be a promising means of improving conditions for patients with
type-2 diabetes?
a.
injections with myostatin
b.
increasing muscle mass
c.
ketoacidosis
d.
injections with acetylcholine
e.
increasing consumption of simple carbohydrates
MATCHING
Match each of the following molecules with its correct description.
a.
Molecules that form a twisted double helix that makes up most of the thin filaments
b.
Neurotransmitters involved in muscle cell contraction
c.
Molecules that block the crossbridge binding sites when the muscle is not contracting
d.
Molecules that make up thick filaments
e.
Molecules that bind to Ca2+, change their shape, and then uncover the crossbridge binding
sites
58. myosin
59. tropomyosin
60. actin
61. troponin
62. acetylcholine
868
Choice
Match the muscle fiber type(s) with the characteristic described. Each choice may be used once, more
than once, or not at all.
a.
slow
b.
fast aerobic
c.
fast anaerobic
d.
both slow and fast aerobic
e.
both fast aerobic and fast anaerobic
63. intermediate glycogen content
64. slow contraction speed
65. high contraction intensity
66. intermediate fatigue resistance
67. high myosin-ATPase activity
68. low oxidative phosphorylation capacity
69. high fatigue resistance
70. many mitochondria
71. low myoglobin content
72. red fiber color
Choice
For each bone type listed, choose the skeleton type(s) to which it belongs. Each choice may be used
once, more than once, or not at all.
a.
axial skeleton
b.
appendicular skeleton
c.
both the axial and the appendicular skeleton
d.
neither the axial nor the appendicular skeleton
73. cranial bones
74. phalanges
75. vertebrae
76. scapula
77. sternum
78. facial bones
79. humerus
80. femur
SHORT ANSWER
81. Describe a toxin that interrupts the crossbridge cycle and other uses for the toxin?
82. Compare and contrast a single, weak contraction of a muscle fiber, a twitch summation, and tetanus.
83. What is the difference between red marrow and yellow marrow?
84. How is movement in vertebrates analogous to the movement of a lever?
MODIFIED TRUE/FALSE
If the statement is true, answer “T”. If the statement is false, answer “F” and make it correct by
changing the underlined word(s) and writing the correct word(s) in the answer blank(s).
85. Skeleton muscles are attached to bones by cords of connective tissue called tendons.
86. The sliding filament model of muscle contraction depends on the dynamic interactions between muscle
and sarcomere proteins.
87. When Ca2+ diffuses into the cytoplasm of muscle cells and initiates the crossbridge cycle, the animal is
most likely stressed.
88. Muscles that can be controlled and precisely and delicately have few muscle fibers.
89. The striated muscles in most invertebrates have thick and thin filaments arranged in sarcomeres
entirely similar to those of vertebrates.
90. In an hydrostatic skeleton, the force of muscle contraction is applied against a rigid, external body
covering.
91. When you collect a sand dollar on the beach, you are looking at the shell of an echinoderm consisting
of ossicles formed from calcium carbonate crystals.
92. The bones of the vertebrate skeleton are connected by flexor joints.
93. Differences in patterns by which muscles connect to bones is relatively invariant in vertebrates.
94. It has recently been illustrated that myostatin can negatively regulate cardiac muscle.