Class Quiz 7
Which of the following is not a function of smooth muscle tissue?
forcing urine out of the urinary tract
altering the diameter of the respiratory passageways
elevating hairs on the arm
forcing blood from the heart into the major arteries
moving food materials along the digestive tract
elevating hairs on the arm
Which of the following surrounds the individual muscle cell?
perimysium
endomysium
epimysium
fasicle
endomysium
When a muscle is unable to respond to stimuli temporarily, it is in
which of
the following periods?
relaxation period
refractory period
latent period
fatigue period
refractory period
The functional role of T-tubules is to?
stabilize the G and F actin
relay the action potential to the interior of the muscle fiber.
hold cross bridges in place in a resting muscle
synthesize ATP to provide energy for muscle contraction
relay the action potential to the interior of the muscle fiber.
Calcium ions bind to the ________ molecule in skeletal muscle cells.
actin
tropomyosin
troponin
myosin
troponin
The complex known as the triad consists of:
actin, myosin and tropomyosin
transverse tubules and terminal cisternae
myofilaments, myofibirils and sarcomeres
A band, H band, and I bands
actin, myosin, and sarcomeres
transverse tubules and terminal cisternae
The sliding filament model of contraction involves:
actin and myosin sliding past each other but not shortening
the shortening of thick filaments so that thin filaments slide past
actin and myosin shortening but not sliding past each other
the Z discs sliding over the myofilaments
actin and myosin sliding past each other but not shortening
Myoglobin:
holds a reserve supply of oxygen in muscle cells
breaks down glycogen
is a protein involved in the direct phosphorylation of ADP
produces the end plate potential
holds a reserve supply of oxygen in muscle cells
The following is a list of the events that occur during a muscle contraction.
1. Myosin cross-bridges bind to the actin.
2. The free myosin
head splits ATP.
3. Calcium ion is released from the sarcoplasmic
reticulum.
4. The myosin head pivots toward the center of the
sarcomere.
5. Calcium ion binds to troponin.
6. The myosin
head binds an ATP molecule and detaches from the actin.
The
correct sequence of these events is
1, 4, 6, 2, 3, 5.
3, 5, 1, 4, 6, 2.
3, 5, 1, 2, 4, 6.
1, 3, 5, 4, 6, 2.
5, 1, 4, 6, 2, 3.
3, 5, 1, 2, 4, 6.
Because skeletal muscle contractions demand large quantities of
ATP,
skeletal muscles have
a rich nerve supply.
a rich blood supply.
abundant mitochondria.
A, B, and C
both B and C
A, B, and C
During anaerobic glycolysis
oxygen is not consumed.
pyruvic acid is produced.
ATP is produced.
all of the above
B and C only
all of the above
The types of muscle tissue include all of the following, except
skeletal muscle.
smooth muscle.
cardiac muscle.
striated muscle.
none of the above
striated muscle.
An excitatory neurotransmitter secreted by motor neurons
innervating
skeletal muscle is:
acetylcholine
gamma aminobutyric acid
cholinesterase
norepinephrine
acetylcholine
The major function of the sarcoplaslmic reticulum in muscle
contraction is
to:
make and store phosphocreatine
synthesis actin and myosin myofilaments
provide a source of myosin for the contraction process
regulate intracellular calcium concentration
regulate intracellular calcium concentration
At rest, active sites on the actin are blocked by:
myosin molecules
troponin molecules
tropomyosin molecules
calcium molecules
ATP molecules
tropomyosin molecules
Creatine phosphate functions in the cell by:
forming a temporary chemical compound with myosin
forming a chemical compound with actin
inducing a conformational change in the myofilaments
storing energy that will be transferred to ADP to resynthesize ATP as needed
storing energy that will be transferred to ADP to resynthesize ATP as needed
Of the following muscle types, which has only one nucleus,
sarcomeres, and
gap junctions?
visceral smooth muscle
multiunit smooth muscle
cardiac muscle
skeletal muscle
cardiac muscle
Which of these would lead to increased oxygen consumption?
increased heat production
increased muscle activity
increased aerobic respiration by muscle cells
increased conversion of lactic acid to glucose
all of the above
all of the above
An anaerobic metabolic pathway that results in the production of two
net
ATP per glucose plus two pyruvic acid molecules is:
the citric acid cycle
glycolysis
hydrolysis
the electron transport system
glycolysis
The functional unit of skeletal muscle is the:
sarcolemma
sarcomere
sarcoplasmic reticulum
myofibril
myofilament
sarcomere