EXAM 3: ANATOMY AND PHYSIOLOGY PRACTICE
TEST
Which type of muscle tissue has the greatest effect on the body's heat
production?
-smooth
-cardiac
-skeletal
-All of these muscle types have about the same effect on the body's heat
production
skeletal
Sarcomere is best defined as...
- a repeating unit of striated muscle
- actomyosin proteins
-a storage form of calcium
-thick and thin filaments
a repeating unit of striated muscle
When a muscle contraction develops tension but doesn't shorten the muscle, the
contraction is called...
-isometric
-unfused tetanus
-isotonic
-incomplete twitch
isometric
Skeletal muscle does each of these except..
-maintain posture
-ventilate the lungs
-pump blood
-produce movement
pump blood
Muscle fatigue occurs due to a buildup of __________ and __________ in pH.
-creatine phosphate; decrease
-creatine phosphate; increase
-lactic acid; increase
-lactic acid; decrease
lactic acid; decrease
All of the following are found in both skeletal and cardiac muscle fibers except...
-intercalated disks
-striations
-mitochondria
-sarcomeres
intercalated disks
Which arrangement of the sarcomere gives rise to the structure (band or line)
indicated by the arrow?
,-the boundary between adjacent sarcomeres
-the region of the resting sarcomere that only contains thick filaments
-is the point of connection for adjacent thick filaments
-the region of the sarcomere that contains only thin filaments
the region of the sarcomere that contains only thin filaments
-The I band extends from the A band of one sarcomere to the A band of the neighboring
sarcomere and is the region where only thin filaments are found.
The Contraction Cycle (Six Steps)
1: Calcium ions arrive within the zone of the overlap.
2: Calcium ions bind to troponin. Active sites on actin are exposed.
3: The myosin heads bind to actin active sites.
4: The myosin head pivots (power stoke). ADP and P are released.
5: ATP binds to the myosin head.
6: The free myosin head "recocks" ADP and P are released.
-The contraction cycle begins with the arrival of calcium ions to the zones of overlap via
excitation-contraction coupling.
-Then, calcium ions bind to the troponin-tropomyosin complex, causing troponin to
change position. Troponin's movement rolls tropomyosin away from actin's active sites,
thus allowing them to form cross-bridges with energized myosin heads. After cross-
bridge formation, the energy that was stored in the resting state is released as the
myosin head pivots towards the M line (coincident with the release of bound ADP and
P). This is known as the power stroke. Finally, to disengage cross-bridges following the
power stroke, ATP binds to the myosin head, and the bond between myosin and actin is
broken. Myosin is reactivated for further cycling when ATP is converted into ADP and P,
and the myosin head returns to its original conformation
Which thick filament binds to actin once its active binding sites are exposed?
- tropomyosin
- actin
- myosin
- troponin
myosin
-Myosin is a thick filament that contains a hinge, allowing its interaction with actin when
binding sites are exposed.
The biochemical reaction that consumes the majority of a muscle's ATP is the...
-neuromuscular transmission
-muscle action potential
-sodium-potassium pump
-actin myosin cross-bridge cycle
actin myosin cross-bridge cycle
Muscles are attached to bones by tendons or...
- ligaments
- aponeuroses
, - perimysium
- superficial fascia
aponeuroses
A thin layer of connective tissue that surrounds a muscle fascicle is called the..
-tendon
-epimysium
-perimysium
-endomysium
perimysium
The dense layer of connective tissue that surrounds an entire skeletal muscle is
the
- fascicle.
- tendon.
-endomysium.
-epimysium.
-perimysium.
epimysium
In a sarcomere, thick filaments are linked laterally by proteins of the
- H band.
- I band.
- M line.
- A band.
- Z line.
M line.
The advantage of having many nuclei in a skeletal muscle fiber is
- the ability to produce nutrients for muscle contraction.
- the ability to contract.
- the ability to produce large amounts of the muscle proteins needed for growth
and repair.
- the ability to produce more ATP with little oxygen.
- the ability to store extra DNA for metabolism.
the ability to produce large amounts of the muscle proteins needed for growth and
repair
Skeletal muscle fibers are formed from embryonic cells called
- fascicles.
- myomeres.
- myofibrils.
- myoblasts.
- sarcomeres.
myoblasts.
The plasma membrane of a skeletal muscle fiber is called the
-sarcosome.
- sarcomere.
- sarcoplasmic reticulum.
- sarcoplasm.
- sarcolemma.
TEST
Which type of muscle tissue has the greatest effect on the body's heat
production?
-smooth
-cardiac
-skeletal
-All of these muscle types have about the same effect on the body's heat
production
skeletal
Sarcomere is best defined as...
- a repeating unit of striated muscle
- actomyosin proteins
-a storage form of calcium
-thick and thin filaments
a repeating unit of striated muscle
When a muscle contraction develops tension but doesn't shorten the muscle, the
contraction is called...
-isometric
-unfused tetanus
-isotonic
-incomplete twitch
isometric
Skeletal muscle does each of these except..
-maintain posture
-ventilate the lungs
-pump blood
-produce movement
pump blood
Muscle fatigue occurs due to a buildup of __________ and __________ in pH.
-creatine phosphate; decrease
-creatine phosphate; increase
-lactic acid; increase
-lactic acid; decrease
lactic acid; decrease
All of the following are found in both skeletal and cardiac muscle fibers except...
-intercalated disks
-striations
-mitochondria
-sarcomeres
intercalated disks
Which arrangement of the sarcomere gives rise to the structure (band or line)
indicated by the arrow?
,-the boundary between adjacent sarcomeres
-the region of the resting sarcomere that only contains thick filaments
-is the point of connection for adjacent thick filaments
-the region of the sarcomere that contains only thin filaments
the region of the sarcomere that contains only thin filaments
-The I band extends from the A band of one sarcomere to the A band of the neighboring
sarcomere and is the region where only thin filaments are found.
The Contraction Cycle (Six Steps)
1: Calcium ions arrive within the zone of the overlap.
2: Calcium ions bind to troponin. Active sites on actin are exposed.
3: The myosin heads bind to actin active sites.
4: The myosin head pivots (power stoke). ADP and P are released.
5: ATP binds to the myosin head.
6: The free myosin head "recocks" ADP and P are released.
-The contraction cycle begins with the arrival of calcium ions to the zones of overlap via
excitation-contraction coupling.
-Then, calcium ions bind to the troponin-tropomyosin complex, causing troponin to
change position. Troponin's movement rolls tropomyosin away from actin's active sites,
thus allowing them to form cross-bridges with energized myosin heads. After cross-
bridge formation, the energy that was stored in the resting state is released as the
myosin head pivots towards the M line (coincident with the release of bound ADP and
P). This is known as the power stroke. Finally, to disengage cross-bridges following the
power stroke, ATP binds to the myosin head, and the bond between myosin and actin is
broken. Myosin is reactivated for further cycling when ATP is converted into ADP and P,
and the myosin head returns to its original conformation
Which thick filament binds to actin once its active binding sites are exposed?
- tropomyosin
- actin
- myosin
- troponin
myosin
-Myosin is a thick filament that contains a hinge, allowing its interaction with actin when
binding sites are exposed.
The biochemical reaction that consumes the majority of a muscle's ATP is the...
-neuromuscular transmission
-muscle action potential
-sodium-potassium pump
-actin myosin cross-bridge cycle
actin myosin cross-bridge cycle
Muscles are attached to bones by tendons or...
- ligaments
- aponeuroses
, - perimysium
- superficial fascia
aponeuroses
A thin layer of connective tissue that surrounds a muscle fascicle is called the..
-tendon
-epimysium
-perimysium
-endomysium
perimysium
The dense layer of connective tissue that surrounds an entire skeletal muscle is
the
- fascicle.
- tendon.
-endomysium.
-epimysium.
-perimysium.
epimysium
In a sarcomere, thick filaments are linked laterally by proteins of the
- H band.
- I band.
- M line.
- A band.
- Z line.
M line.
The advantage of having many nuclei in a skeletal muscle fiber is
- the ability to produce nutrients for muscle contraction.
- the ability to contract.
- the ability to produce large amounts of the muscle proteins needed for growth
and repair.
- the ability to produce more ATP with little oxygen.
- the ability to store extra DNA for metabolism.
the ability to produce large amounts of the muscle proteins needed for growth and
repair
Skeletal muscle fibers are formed from embryonic cells called
- fascicles.
- myomeres.
- myofibrils.
- myoblasts.
- sarcomeres.
myoblasts.
The plasma membrane of a skeletal muscle fiber is called the
-sarcosome.
- sarcomere.
- sarcoplasmic reticulum.
- sarcoplasm.
- sarcolemma.
