DE A&P Chapter 7 Muscular System ANSWERS || 100%
CORRECT
A. Label the diagrams of the muscle tissue. List three structural features of each type of
muscle tissue and the location in the body where each type is found. correct answers 1. Name
of tissue: Skeletal Muscle
Features: Voluntary, Striated, Packed close together
Location: Virtually all bones of the skeleton
2. Name of tissue: Smooth Muscle
Features: Involuntary, nonstriated, greater amount of actin
Location: Walls of hollow internal structures (blood vessels, airways, abdominopelvic
organs)
3. Name of tissue: Cardiac Muscle
Features: Involuntary, Striated, Joined at intercalated disks
Location: Only in the heart
B. Name the four common characteristics of the muscle cells. correct answers Contractibility,
excitability, extensibility, elasticity
C. Place the correct word or words next to the following statements; make a selection from
the list provided.
1. A characteristic shared with nerve cells; the ability to respond to a stimulus.
_____________
2. This structure contains membranes fused at places called intercalated disks; a
communication system at the fused area will not permit the cells to act independently.
_____________
3. The ability of a muscle to return to its original length after stretching. _____________
4. The ability of muscles to be stretched. _____________
5. Muscles only pull and never push; they are attached to the bones of the skeleton by
nonelastic cords. _____________
6. The part of the muscle attached to a fixed point on the bones; the least movable part during
a contraction. _____________
7. This muscle has the ability to cause the diameter of blood vessels to decrease on
contraction. _____________
8. Muscles that open and close to correct answers 1. excitability
2. cardiac muscle
3. elasticity
4. extensibility
5. tendons
6. origin
7. smooth muscle
8. dilator
9. contractility
10. insertion
, D. Using the following words, complete the story about the steps in muscle contraction.
Words may be used once. (some may be wrong..)
For muscles to work, they need a stimulus from a __________ nerve and a source of energy
that is __________ __________, also known __________. The muscle cell also requires
oxygen and __________.
Between the nerve cell's fiber, the axon, and the muscle cell is a neuromuscular junction
called the __________ __________. When the nerve impulse reaches the end of the axon, it
releases a chemical called __________. This chemical diffuses across the junction and
attaches to the cell membrane, the __________. This action makes the membrane temporarily
permeable to __________. The muscle cell now has excessive positive ions, which upset the
electrical condition; this electrical upset causes a(n) __________ __________.
Skeletal muscle contraction begins with the action potential that travels correct answers
motor
adenosine triphosphate
ATP
glucose
synaptic cleft
neurotransmitter
sarcolemma
sodium
action potential
length
contraction
original
positive
lactic acid
fatigue
cramps
pain
E. Circle the correct word in the following statements about muscle tone.
1. Muscles are (always, sometimes, never) in a state of partial contraction.
2. In an isometric contraction, the tension in a muscle (decreases, increases, stays the same),
and the muscle (does, does not) shorten.
3. In an isotonic muscle contraction, the muscle (does, does not) shorten.
4. When muscles are flaccid, they are (weak, strong).
5. In atrophy, the muscle (increases, decreases) in size from disuse.
6. In hypertrophy, the size of the muscle (shrinks, enlarges) correct answers 1. always
2. stays the same; does not
3. does
4. weak
5. decreases
6. enlarges
CORRECT
A. Label the diagrams of the muscle tissue. List three structural features of each type of
muscle tissue and the location in the body where each type is found. correct answers 1. Name
of tissue: Skeletal Muscle
Features: Voluntary, Striated, Packed close together
Location: Virtually all bones of the skeleton
2. Name of tissue: Smooth Muscle
Features: Involuntary, nonstriated, greater amount of actin
Location: Walls of hollow internal structures (blood vessels, airways, abdominopelvic
organs)
3. Name of tissue: Cardiac Muscle
Features: Involuntary, Striated, Joined at intercalated disks
Location: Only in the heart
B. Name the four common characteristics of the muscle cells. correct answers Contractibility,
excitability, extensibility, elasticity
C. Place the correct word or words next to the following statements; make a selection from
the list provided.
1. A characteristic shared with nerve cells; the ability to respond to a stimulus.
_____________
2. This structure contains membranes fused at places called intercalated disks; a
communication system at the fused area will not permit the cells to act independently.
_____________
3. The ability of a muscle to return to its original length after stretching. _____________
4. The ability of muscles to be stretched. _____________
5. Muscles only pull and never push; they are attached to the bones of the skeleton by
nonelastic cords. _____________
6. The part of the muscle attached to a fixed point on the bones; the least movable part during
a contraction. _____________
7. This muscle has the ability to cause the diameter of blood vessels to decrease on
contraction. _____________
8. Muscles that open and close to correct answers 1. excitability
2. cardiac muscle
3. elasticity
4. extensibility
5. tendons
6. origin
7. smooth muscle
8. dilator
9. contractility
10. insertion
, D. Using the following words, complete the story about the steps in muscle contraction.
Words may be used once. (some may be wrong..)
For muscles to work, they need a stimulus from a __________ nerve and a source of energy
that is __________ __________, also known __________. The muscle cell also requires
oxygen and __________.
Between the nerve cell's fiber, the axon, and the muscle cell is a neuromuscular junction
called the __________ __________. When the nerve impulse reaches the end of the axon, it
releases a chemical called __________. This chemical diffuses across the junction and
attaches to the cell membrane, the __________. This action makes the membrane temporarily
permeable to __________. The muscle cell now has excessive positive ions, which upset the
electrical condition; this electrical upset causes a(n) __________ __________.
Skeletal muscle contraction begins with the action potential that travels correct answers
motor
adenosine triphosphate
ATP
glucose
synaptic cleft
neurotransmitter
sarcolemma
sodium
action potential
length
contraction
original
positive
lactic acid
fatigue
cramps
pain
E. Circle the correct word in the following statements about muscle tone.
1. Muscles are (always, sometimes, never) in a state of partial contraction.
2. In an isometric contraction, the tension in a muscle (decreases, increases, stays the same),
and the muscle (does, does not) shorten.
3. In an isotonic muscle contraction, the muscle (does, does not) shorten.
4. When muscles are flaccid, they are (weak, strong).
5. In atrophy, the muscle (increases, decreases) in size from disuse.
6. In hypertrophy, the size of the muscle (shrinks, enlarges) correct answers 1. always
2. stays the same; does not
3. does
4. weak
5. decreases
6. enlarges
