Deck 9: Muscular System

Full screen (f)
exit full mode
Question
What are fascicles?

A) Muscle cells
B) Groups of muscle fibers
C) Types of tendons
D) Neurons that innervate muscles
Use Space or
up arrow
down arrow
to flip the card.
Question
What is an aponeurosis?

A) A strong, fibrous cord that attaches muscle to bone
B) Connective tissue that covers each muscle fiber
C) Connective tissue that surrounds the muscle outside the epimysium
D) A flat, broad tendon that attaches muscle to another muscle
Question
What is the name of the connective tissue that surrounds the muscle as a whole?

A) Endomysium
B) Epimysium
C) Perimysium
D) Periosteum
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
One of the bulging muscles of the calf
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Flexes the head
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Abducts, flexes, and rotates the arm
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
The longest muscle in the body; aids in flexion of the hip and knee
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Raises and lowers the shoulders
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
The prime mover when flexing the forearm
Question
What is the delicate connective tissue that covers each muscle fiber?

A) Endomysium
B) Epimysium
C) Perimysium
D) Periosteum
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Raises the eyebrows when glancing upward
Question
Which of the following correctly describes skeletal muscle?

A) It is known as voluntary muscle.
B) It consists of short, branching fibers that fit together at intercalated discs.
C) It is found in the digestive tract, blood vessels, and airways.
D) It is called nonstriated because it does not appear striped when examined under a microscope.
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Elevate the ribs during inspiration
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Flexes and adducts the upper arm, such as when climbing or hugging
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
The prime mover when extending the forearm
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
The most powerful muscle in the body
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Adducts the humerus and extends the upper arm backward, such as when climbing or swimming
Question
How does muscle attach to muscle?

A) Muscle fibers of one muscle merge with the fibers of the other muscle.
B) The epimysium extends past the muscle and merges with the epimysium of the other muscle.
C) The epimysium extends past the muscle as a flat sheet of connective tissue that fuses with the covering of the other muscle.
D) Muscle does not attach to muscle; it only attaches to bone.
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Flexes the thigh
Question
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Flexes the lumbar region of the spinal cord to cause bending over at the waist
Question
Which factor influences the strength with which a muscle fiber contracts?

A) The amount of acetylcholine released into the synaptic cleft
B) The amount of calcium released
C) The length of the muscle fiber before the contraction begins
D) The size of the muscle fiber
Question
How do the muscles of a sprinter running the 400-yard dash in 50 seconds receive most of their energy?

A) The aerobic respiration of fatty acids
B) The breakdown of creatine phosphate
C) The anaerobic respiration of glucose
D) The aerobic respiration of glucose
Question
According to the sliding-filament model of contraction, how does muscle contraction occur?

A) The myosin heads propel the actin myofilaments toward the center of the sarcomere; this pulls the Z disks closer together, which shortens the sarcomere and the entire muscle.
B) The actin heads propel the myosin filaments toward the center of the sarcomere; this pulls the Z disks closer together, which shortens the sarcomere and the entire muscle.
C) The myosin heads propel the actin myofilaments toward the center of the sarcomere. This causes the myofilaments to shorten, which pulls the Z disks closer together to shorten the sarcomere and the entire muscle.
D) Both the actin and myosin myofilaments shorten, which shrinks the sarcomere and pulls the Z disks closer together. As the Z disks move closer together, the muscle contracts.
Question
If impulses reach a muscle fiber so rapidly that fibers don't have a chance to relax completely before the next impulse arrives, what condition will occur?

A) Twitch
B) Treppe
C) Incomplete tetanus
D) Complete tetanus
Question
Which statement correctly describes the sequence of events in muscle contraction?

A) An impulse triggers the release of acetylcholine (ACh), which diffuses across the synaptic cleft to stimulate the sarcolemma to release ATP. The ATP triggers the actin and myosin filaments to shorten, and muscle contraction occurs.
B) An impulse triggers the release of acetylcholinesterase into the synaptic cleft. This causes calcium ions to be pumped into the T tubules. The calcium allows the myosin heads to latch on to the actin filaments and muscle contraction occurs.
C) An impulse triggers the release of acetylcholine (ACh), which diffuses across the synaptic cleft to stimulate the T tubules to release calcium. The calcium binds with troponin on the actin filaments, which permits the myosin heads to latch on and muscle contraction occurs.
D) An impulse triggers the release of acetylcholine (ACh). This stimulates the sarcolemma, which sends an impulse to the actin and myosin filaments. The myosin heads then latch on to the actin filaments, pulling the Z disks closer together, and muscle contraction occurs.
Question
In the disease myasthenia gravis, the body produces antibodies against receptors for acetylcholine (ACh). As a result, not all ACh can find a receptor. Based on your knowledge of how muscle contraction occurs, what key symptoms would you expect to see and why?

A) Paralysis, because all ACh must be bound to a receptor for contraction to occur
B) Tetany, because the muscle will fire excessively as the ACh attempts to find a receptor
C) Weakness, because not all of the AChs will find a receptor, resulting in poor nerve transmission
D) Muscle spasms, because the ACh remaining in the synaptic cleft will irritate the receiving nerve
Question
The plasma membrane that surrounds a muscle fiber is called a ____________________.
Question
How do muscles obtain their energy after about 10 minutes of moderate exercise, and what benefit does it have over other methods?

A) Muscles obtain their energy by metabolizing fatty acids; this is beneficial because fatty acids are plentiful.
B) Muscles obtain their energy through anaerobic respiration of glucose; this is beneficial because anaerobic respiration can generate energy quickly.
C) Muscles obtain their energy through aerobic respiration of glucose; this is useful because it produces more ATP than anaerobic respiration.
D) Muscles obtain their energy by breaking down ATP; this is useful because creatine phosphate is plentiful.
Question
Most skeletal muscles remain in a state of

A) relaxation.
B) treppe.
C) incomplete tetanus.
D) complete tetanus.
Question
When extending the forearm

A) the triceps brachii is the prime mover, and the brachialis is the synergist.
B) the triceps brachii is the synergist, and the brachialis is the prime mover.
C) the triceps brachii is the prime mover, and the brachialis is the antagonist.
D) the triceps brachii is the antagonist, and the brachialis is the prime mover.
Question
What is the chief function of T tubules?

A) They allow electrical impulses to travel deep into the cell.
B) They store the calcium ions necessary for muscle contraction.
C) They contain myofilaments necessary for muscle contraction.
D) They store glycogen and oxygen.
Question
Between the end of a motor nerve and a muscle fiber is a narrow space called a ____________________.
Question
Thick myofilaments consist of a protein called ____________________, whereas thin myofilaments consist of a protein called ____________________.
Question
The continuous state of partial contraction that allows you to stand and hold your head up is called ____________________.
Question
A skeletal muscle cell is called a ____________________.
Question
What are the units of contraction in a muscle called?

A) Myofilaments
B) Z lines
C) Sarcomeres
D) Sarcolemmas
Question
The connective tissue surrounding the muscle outside the epimysium is called ____________________.
Question
The epimysium of a muscle sometimes extends past as a flat sheet of connective tissue called an ____________________ that then fuses with the covering of another muscle.
Question
Besides ATP, muscle contraction requires

A) sodium.
B) potassium.
C) calcium.
D) tropomyosin and troponin.
Question
What are myofibrils?

A) Long protein bundles that fill the sarcoplasm and store glycogen
B) The membrane surrounding each muscle fiber
C) Tubules that allow electrical impulses to travel into the muscle cell
D) Another name for muscle cells
Question
The minimum voltage needed to cause a muscle fiber to contract is called the ____________________.
Question
In an ____________________ contraction, the tension in the muscle increases whereas its length remains the same.
Question
Anaerobic respiration produces a by-product called ____________________ that leads to muscle ____________________.
Question
A lack of use causes a muscle to shrink, or ____________________.
Question
In an ____________________ contraction, the muscle changes length to move a load whereas the tension in the muscle remains the same.
Question
A neuron and all the fibers it stimulates are called a ____________________.
Question
The end of the muscle that attaches to the more stationary bone is called the ____________________, whereas the end with the more mobile attachment is called the ____________________.
Unlock Deck
Sign up to unlock the cards in this deck!
Unlock Deck
Unlock Deck
1/47
auto play flashcards
Play
simple tutorial
Full screen (f)
exit full mode
Deck 9: Muscular System
1
What are fascicles?

A) Muscle cells
B) Groups of muscle fibers
C) Types of tendons
D) Neurons that innervate muscles
B
2
What is an aponeurosis?

A) A strong, fibrous cord that attaches muscle to bone
B) Connective tissue that covers each muscle fiber
C) Connective tissue that surrounds the muscle outside the epimysium
D) A flat, broad tendon that attaches muscle to another muscle
D
3
What is the name of the connective tissue that surrounds the muscle as a whole?

A) Endomysium
B) Epimysium
C) Perimysium
D) Periosteum
B
4
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
One of the bulging muscles of the calf
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
5
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Flexes the head
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
6
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Abducts, flexes, and rotates the arm
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
7
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
The longest muscle in the body; aids in flexion of the hip and knee
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
8
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Raises and lowers the shoulders
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
9
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
The prime mover when flexing the forearm
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
10
What is the delicate connective tissue that covers each muscle fiber?

A) Endomysium
B) Epimysium
C) Perimysium
D) Periosteum
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
11
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Raises the eyebrows when glancing upward
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
12
Which of the following correctly describes skeletal muscle?

A) It is known as voluntary muscle.
B) It consists of short, branching fibers that fit together at intercalated discs.
C) It is found in the digestive tract, blood vessels, and airways.
D) It is called nonstriated because it does not appear striped when examined under a microscope.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
13
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Elevate the ribs during inspiration
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
14
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Flexes and adducts the upper arm, such as when climbing or hugging
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
15
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
The prime mover when extending the forearm
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
16
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
The most powerful muscle in the body
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
17
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Adducts the humerus and extends the upper arm backward, such as when climbing or swimming
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
18
How does muscle attach to muscle?

A) Muscle fibers of one muscle merge with the fibers of the other muscle.
B) The epimysium extends past the muscle and merges with the epimysium of the other muscle.
C) The epimysium extends past the muscle as a flat sheet of connective tissue that fuses with the covering of the other muscle.
D) Muscle does not attach to muscle; it only attaches to bone.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
19
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Flexes the thigh
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
20
Match each muscle with its function or description.
a.sternocleidomastoid
j.latissimus dorsi
b.frontalis
k.brachialis
c.trapezius
l.triceps brachii
d.external intercostals
m.brachioradialis
e.internal intercostals
n.quadriceps femoris
f.rectus abdominis
o.sartorius
g.transverse abdominal
p.iliopsoas
h.deltoid
q.gastrocnemius
i.pectoralis major
Flexes the lumbar region of the spinal cord to cause bending over at the waist
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
21
Which factor influences the strength with which a muscle fiber contracts?

A) The amount of acetylcholine released into the synaptic cleft
B) The amount of calcium released
C) The length of the muscle fiber before the contraction begins
D) The size of the muscle fiber
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
22
How do the muscles of a sprinter running the 400-yard dash in 50 seconds receive most of their energy?

A) The aerobic respiration of fatty acids
B) The breakdown of creatine phosphate
C) The anaerobic respiration of glucose
D) The aerobic respiration of glucose
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
23
According to the sliding-filament model of contraction, how does muscle contraction occur?

A) The myosin heads propel the actin myofilaments toward the center of the sarcomere; this pulls the Z disks closer together, which shortens the sarcomere and the entire muscle.
B) The actin heads propel the myosin filaments toward the center of the sarcomere; this pulls the Z disks closer together, which shortens the sarcomere and the entire muscle.
C) The myosin heads propel the actin myofilaments toward the center of the sarcomere. This causes the myofilaments to shorten, which pulls the Z disks closer together to shorten the sarcomere and the entire muscle.
D) Both the actin and myosin myofilaments shorten, which shrinks the sarcomere and pulls the Z disks closer together. As the Z disks move closer together, the muscle contracts.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
24
If impulses reach a muscle fiber so rapidly that fibers don't have a chance to relax completely before the next impulse arrives, what condition will occur?

A) Twitch
B) Treppe
C) Incomplete tetanus
D) Complete tetanus
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
25
Which statement correctly describes the sequence of events in muscle contraction?

A) An impulse triggers the release of acetylcholine (ACh), which diffuses across the synaptic cleft to stimulate the sarcolemma to release ATP. The ATP triggers the actin and myosin filaments to shorten, and muscle contraction occurs.
B) An impulse triggers the release of acetylcholinesterase into the synaptic cleft. This causes calcium ions to be pumped into the T tubules. The calcium allows the myosin heads to latch on to the actin filaments and muscle contraction occurs.
C) An impulse triggers the release of acetylcholine (ACh), which diffuses across the synaptic cleft to stimulate the T tubules to release calcium. The calcium binds with troponin on the actin filaments, which permits the myosin heads to latch on and muscle contraction occurs.
D) An impulse triggers the release of acetylcholine (ACh). This stimulates the sarcolemma, which sends an impulse to the actin and myosin filaments. The myosin heads then latch on to the actin filaments, pulling the Z disks closer together, and muscle contraction occurs.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
26
In the disease myasthenia gravis, the body produces antibodies against receptors for acetylcholine (ACh). As a result, not all ACh can find a receptor. Based on your knowledge of how muscle contraction occurs, what key symptoms would you expect to see and why?

A) Paralysis, because all ACh must be bound to a receptor for contraction to occur
B) Tetany, because the muscle will fire excessively as the ACh attempts to find a receptor
C) Weakness, because not all of the AChs will find a receptor, resulting in poor nerve transmission
D) Muscle spasms, because the ACh remaining in the synaptic cleft will irritate the receiving nerve
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
27
The plasma membrane that surrounds a muscle fiber is called a ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
28
How do muscles obtain their energy after about 10 minutes of moderate exercise, and what benefit does it have over other methods?

A) Muscles obtain their energy by metabolizing fatty acids; this is beneficial because fatty acids are plentiful.
B) Muscles obtain their energy through anaerobic respiration of glucose; this is beneficial because anaerobic respiration can generate energy quickly.
C) Muscles obtain their energy through aerobic respiration of glucose; this is useful because it produces more ATP than anaerobic respiration.
D) Muscles obtain their energy by breaking down ATP; this is useful because creatine phosphate is plentiful.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
29
Most skeletal muscles remain in a state of

A) relaxation.
B) treppe.
C) incomplete tetanus.
D) complete tetanus.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
30
When extending the forearm

A) the triceps brachii is the prime mover, and the brachialis is the synergist.
B) the triceps brachii is the synergist, and the brachialis is the prime mover.
C) the triceps brachii is the prime mover, and the brachialis is the antagonist.
D) the triceps brachii is the antagonist, and the brachialis is the prime mover.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
31
What is the chief function of T tubules?

A) They allow electrical impulses to travel deep into the cell.
B) They store the calcium ions necessary for muscle contraction.
C) They contain myofilaments necessary for muscle contraction.
D) They store glycogen and oxygen.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
32
Between the end of a motor nerve and a muscle fiber is a narrow space called a ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
33
Thick myofilaments consist of a protein called ____________________, whereas thin myofilaments consist of a protein called ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
34
The continuous state of partial contraction that allows you to stand and hold your head up is called ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
35
A skeletal muscle cell is called a ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
36
What are the units of contraction in a muscle called?

A) Myofilaments
B) Z lines
C) Sarcomeres
D) Sarcolemmas
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
37
The connective tissue surrounding the muscle outside the epimysium is called ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
38
The epimysium of a muscle sometimes extends past as a flat sheet of connective tissue called an ____________________ that then fuses with the covering of another muscle.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
39
Besides ATP, muscle contraction requires

A) sodium.
B) potassium.
C) calcium.
D) tropomyosin and troponin.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
40
What are myofibrils?

A) Long protein bundles that fill the sarcoplasm and store glycogen
B) The membrane surrounding each muscle fiber
C) Tubules that allow electrical impulses to travel into the muscle cell
D) Another name for muscle cells
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
41
The minimum voltage needed to cause a muscle fiber to contract is called the ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
42
In an ____________________ contraction, the tension in the muscle increases whereas its length remains the same.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
43
Anaerobic respiration produces a by-product called ____________________ that leads to muscle ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
44
A lack of use causes a muscle to shrink, or ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
45
In an ____________________ contraction, the muscle changes length to move a load whereas the tension in the muscle remains the same.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
46
A neuron and all the fibers it stimulates are called a ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
47
The end of the muscle that attaches to the more stationary bone is called the ____________________, whereas the end with the more mobile attachment is called the ____________________.
Unlock Deck
Unlock for access to all 47 flashcards in this deck.
Unlock Deck
k this deck
locked card icon
Unlock Deck
Unlock for access to all 47 flashcards in this deck.