Chapter 8: Muscular system Flashcards
The sarcolemma of muscle cells is equivalent to the ………. of other cells.
a. cytoplasm
b. nucleus
c. plasma membrane
d. endoplasmic reticulum
e. mitochondria
c. plasma membrane
the connective tissue component that surrounds fascicles is the….
a. endomysium
b. sacroplasmic reticulum
c. fascia
d. epimysium
e. perimysium
e. perimysium
Which of the following statements about skeletal muscle tissue is NOT true?
a. skeletal muscle requires a large blood supply.
b. skeletal muscle fibers have many mitochondria
c. the arrengement of thich and thin filaments produces the striations in skeletal muscle tissue.
d. skeletal muscle fibers contain gap junctions that help conduct action potentials from one fiber to another.
e. a skeletal muscle fiber has many nuclei
d. skeletal muscle fibers contain gap junctions that help conduct action potentials from one fiber to another.
Match the following:
………..; network of tubules that stores calcium
sarcoplasmic reticulum
Match the following:
………..; pigment that stores oxygen
myoglobin
Match the following:
………..; composed of myosin
thick filaments
Match the following:
………..; composed of actin, tropomyosin and troponin
thin filaments
Match the following:
………..; tunnel-like extensions of sarcolemma
transverse tabules
The reddish color of slow oxidative and fast oxidative-glycolytic skeletal muscle fibers is due to…
a. the mitochondria.
b. the large amount of myoglobin.
c. the presence of large numbers of myofibrils.
d. blood.
e. genetics.
b. the large amount of myoglobin.
You begin an intensive weightlifting plan because you want to enter a weightlifting contest. During the activity of weightlifting, your skeletal muscles will obtain energy (ATP) primarily through…
a. anaerobic glycosis
b. the complete breakdown of pyruvic acid in the mitochondria.
c. creatine phosphate
d. faster breathing
e. aerobic cellular respiration.
a. anaerobic glycosis
Muscle contractions are smooth, coordinated movements because of…
a. motor unit recruitment
b. wave summation
c. tetanic contractions
d. the presence of fast oxidative-glycolytic fibers
e. latent periods
a. motor unit recruitment
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
involuntary
cardiac and smooth
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
multinucleated
skeletal
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
striated
skeletal and cardiac
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
contain intercalated discs
cardiac
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
elongated, cylindrical cells
skeletal
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
voluntary
skeletal
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
cells that taper at both ends
smooth
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
nonstriated
smooth
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
muscle fibers contract individually
skeletal, some smooth
Does the following refer to skeletal muscle, cardiac muscle or smooth muscle?
autorhytmic
cardiac, some smooth
When ATP in the sarcoplasm is exhausted, the muscle must rely on ………. to quickly produce more ATP from ADP for contraction.
a. acetylcholine
b. creatine phosphate
c. lactic acid
d. pyruvic acid
e. acetylcholinesterase
b. creatine phosphate
A motor unit consists of…
a. a transverse tubule and its associated sarcomeres
b. a motor neuron and all of the muscle fibers it stimulates.
c. a muscle and all of its motor neurons.
d. all of the filaments encased within a sarcomere.
e. the motor end plate and the transverse tubules.
b. a motor neuron and all of the muscle fibers it stimulates.
Thick filaments…
a. include actin, troponin and tropomyosin
b. compose the I band
c. stretch the entire length of a sarcomere.
d. have binding sites for Ca^2+
e. have myosin heads used for the power stroke
e. have myosin heads used for the power stroke
The chemical that prevents the continuous stimulation of a muscle fiber is…
a. Ca^2+
b. acetylcholinesterase
c. ATP
d. acetylcholine
e. actin
b. acetylcholinesterase
Which of the following is NOT associated with muscle fatique?
a. depletion of creatine phosphate
b. lack of oxygen
c. decrease in CA^2+ levels in the sarcoplasm
d. decrease in lactid acid levels
e. lack of glycogen
d. decrease in lactid acid levels
Which of the following binds to Ca^2+ ?
a. actin
b. troponin
c. tropomyosin
d. myosin
e. acetylcholine
b. troponin
Skeletal muscles are named using several characteristics. Which characteristic is NOT used to name skeletal muscles?
a. direction of fibers
b. size
c. speed of contraction
d. location
e. shape
c. speed of contraction
Arrange the following in the correct order for skeletal muscle fiber contraction.
- sarcoplasmic reticulum releases Ca^2+.
- Ca^2+ combines with troponin, uncovering myosin-binding sites.
- acetylcholine is released from the axon terminal and binds to receptors in the motor end plate.
- action potential travels along the sarcolemma and into transverse tubes.
- energized myosin heads (crossbridges) attach to actin.
- thin filaments slide toward the center of the sarcomere.
a. 3, 4, 1, 2, 5, 6
b. 4, 3, 2, 1, 5, 6
c. 1, 2, 3, 4, 5, 6
d. 4, 1, 3, 5, 2, 6
e. 3, 1, 4, 5, 2, 6
a. 3, 4, 1, 2, 5, 6
What would happen if ATP were suddenly unavailable after the sarcomere had begun to shorten?
a. nothing. the contraction would proceed normally.
b. the myosin heads would be unable to detach from actin.
c. troponin would bind with the myosin heads.
d. actin and myosin filaments would separate completely and be unable to recombine.
e. the myosin heads would detach completely from actin and bind to the troponin-tropomyosin complex.
b. the myosin heads would be unable to detach from actin.
Match the following with the right name:
……….: extend from the thick filaments.
myosin heads
Match the following with the right name:
……….: contain myosin-binding sites
actin molecules
Match the following with the right name:
……….: dense area of protein that separates sarcomeres
Z discs
Match the following with the right name:
……….: contain acetylcholine
synaptic vesicles
Match the following with the right name:
……….: striated zone of the sarcomere composed of thick and thin filaments
A band
Match the following with the right name:
……….: space between axon terminal and the sarcolemma
synaptic cleft
Match the following with the right name:
……….: striated zone of the sarcomere composed of thin filaments only
I band
Match the following with the right name:
……….: region of sarcolemma near the adjoining axon terminal
motor end plate
Match the following with the right name:
……….: works with prime mover to reduce unnecessary movement
synergist
Match the following with the right name:
……….: muscle in a group that contracts to produce desired movement
prime mover
Match the following with the right name:
……….: stationary end of a muscle.
origin
Match the following with the right name:
……….: muscle that has an action opposite to that of another muscle
antagonist
Match the following with the right name:
……….: helps stabilize the origin of the prime mover
fixator
Match the following with the right name:
……….: the end of a muscle attached to the movable bone
insertion
