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