ANATOMY AND PHYSIOLOGY
EXAM 3 WITH 100% CORRECT
ANSWERS 2025/2026
Sarcolemma correct answers >> muscle plasma membrane
Sarcoplasm correct answers >> cytoplasm of a muscle cell
Muscle cells respond to neural, stretch, or other signals by
changing their _______. correct answers >> sarcolemma
electrical potential (voltage)
The electrical potential change is coupled to intracellular changes
that result in ______. correct answers >> force generation
(contraction)
Contractility correct answers >> active shortening of muscle
cell and generation of tension (force)
Extensibility correct answers >> passive stretching of muscle
cells
Elasticity correct answers >> return of muscle cells to
original resting length after being stretched
Which muscle tissue(s) has cells w/ obvious stripes called
striations correct answers >> skeletal, cardiac
,Which muscle tissue is voluntary and which is involuntary?
correct answers >> voluntary-skeletal......involuntary-
cardiac,smooth
What muscle tissue contracts rapidly but tires easily? correct
answers >> skeletal
Cardiac muscle contracts at a rate set by the heart's ________.
correct answers >> pacemaker
Which muscle tissue is primarily found in the walls of hollow
visceral organs? correct answers >> smooth
Which muscle tissue forces food and other substances through
internal body cavities? correct answers >> smooth
What are the three connective tissue sheaths? correct answers
>> endomysium, perimysium, epimysium
What is a fine sheath of connective tissue composed of reticular
fibers surrounding each muscle fiber? correct answers >>
endomysium
What is fibrous connective tissue that surrounds groups of muscle
fibers called fascicles? correct answers >> perimysium
What is an overcoat of dense regular connective tissue that
surrounds the entire muscle? correct answers >> epimysium
,each muscle is served by ________. correct answers >> one
nerve(bundle of nerve fibers), an atery, and one or more veins
when muscles contract... correct answers >> the movable
bone (insertion) moves toward the immovable bone (origin)
How does a muscle attach to a bone directly? correct answers
>> epimysium of the muscle is fused to the periosteum of a
bone (less common)
How does a muscle attach to a bone indirectly? correct
answers >> connective tissue wrappings extend beyond the
muscle as a tendon or aponeurosis that attaches to a bone (more
common)
What is a single muscle cell called? correct answers >> a
myocyte or muscle fiber
Myocyte size correct answers >> 10 to 100 micrometers in
diamter and many 10s of cm long
Each mature myocyte is created by fusion of multiple precursor
cells called _________. correct answers >> myoblasts
Sarcoplasm has numerous ________ and an oxygen-binding protein
called _________. correct answers >> glycosomes, myoglobin
, Myocytes contain the usual organelles, as well as.... correct
answers >> myofibrils, sarcoplasmic reticulum, T-tubules
Densly packed rodlike contractile elements are called ________.
correct answers >> myofibrils
What is the smallest contractile unit of a muscle called?
correct answers >> a sarcomere
What is the region of a myofibril b/w two succesive Z-discs?
correct answers >> a sarcomere
What is a sarcomere composed of? correct answers >> thick
and thin myofilaments made up of contractile proteins
How long does a thick filament of a myofilament extend? A thin
filament? correct answers >> thick: the entire length of an A-
band
thin:across the I band and part way into the A band
What is a coin-shaped sheet of proteins (connectins) that anchors
the thin filaments and connects myofibrils? correct answers
>> Z-disc
Where do elastic filaments stretch and what are they made of?
correct answers >> from Z-disc through the thick filament to the
M-line.
a huge protein called titin.
EXAM 3 WITH 100% CORRECT
ANSWERS 2025/2026
Sarcolemma correct answers >> muscle plasma membrane
Sarcoplasm correct answers >> cytoplasm of a muscle cell
Muscle cells respond to neural, stretch, or other signals by
changing their _______. correct answers >> sarcolemma
electrical potential (voltage)
The electrical potential change is coupled to intracellular changes
that result in ______. correct answers >> force generation
(contraction)
Contractility correct answers >> active shortening of muscle
cell and generation of tension (force)
Extensibility correct answers >> passive stretching of muscle
cells
Elasticity correct answers >> return of muscle cells to
original resting length after being stretched
Which muscle tissue(s) has cells w/ obvious stripes called
striations correct answers >> skeletal, cardiac
,Which muscle tissue is voluntary and which is involuntary?
correct answers >> voluntary-skeletal......involuntary-
cardiac,smooth
What muscle tissue contracts rapidly but tires easily? correct
answers >> skeletal
Cardiac muscle contracts at a rate set by the heart's ________.
correct answers >> pacemaker
Which muscle tissue is primarily found in the walls of hollow
visceral organs? correct answers >> smooth
Which muscle tissue forces food and other substances through
internal body cavities? correct answers >> smooth
What are the three connective tissue sheaths? correct answers
>> endomysium, perimysium, epimysium
What is a fine sheath of connective tissue composed of reticular
fibers surrounding each muscle fiber? correct answers >>
endomysium
What is fibrous connective tissue that surrounds groups of muscle
fibers called fascicles? correct answers >> perimysium
What is an overcoat of dense regular connective tissue that
surrounds the entire muscle? correct answers >> epimysium
,each muscle is served by ________. correct answers >> one
nerve(bundle of nerve fibers), an atery, and one or more veins
when muscles contract... correct answers >> the movable
bone (insertion) moves toward the immovable bone (origin)
How does a muscle attach to a bone directly? correct answers
>> epimysium of the muscle is fused to the periosteum of a
bone (less common)
How does a muscle attach to a bone indirectly? correct
answers >> connective tissue wrappings extend beyond the
muscle as a tendon or aponeurosis that attaches to a bone (more
common)
What is a single muscle cell called? correct answers >> a
myocyte or muscle fiber
Myocyte size correct answers >> 10 to 100 micrometers in
diamter and many 10s of cm long
Each mature myocyte is created by fusion of multiple precursor
cells called _________. correct answers >> myoblasts
Sarcoplasm has numerous ________ and an oxygen-binding protein
called _________. correct answers >> glycosomes, myoglobin
, Myocytes contain the usual organelles, as well as.... correct
answers >> myofibrils, sarcoplasmic reticulum, T-tubules
Densly packed rodlike contractile elements are called ________.
correct answers >> myofibrils
What is the smallest contractile unit of a muscle called?
correct answers >> a sarcomere
What is the region of a myofibril b/w two succesive Z-discs?
correct answers >> a sarcomere
What is a sarcomere composed of? correct answers >> thick
and thin myofilaments made up of contractile proteins
How long does a thick filament of a myofilament extend? A thin
filament? correct answers >> thick: the entire length of an A-
band
thin:across the I band and part way into the A band
What is a coin-shaped sheet of proteins (connectins) that anchors
the thin filaments and connects myofibrils? correct answers
>> Z-disc
Where do elastic filaments stretch and what are they made of?
correct answers >> from Z-disc through the thick filament to the
M-line.
a huge protein called titin.
