Bio 264 Exam 3 Questions with 100% Verified
Correct Answers
What structure runs from Z line to Z line?
Sarcomere
The movement of the troponin-tropomyosin complex requires _______
Ca2+.
The actin filament is a polymer formed from 300 to 400 globular subunits called ______
G-actin.
A myofilament is the _________.
Protein strand composed of actin or myosin
T tubules ________.
Conduct action potentials deep into the muscle cell
A drug that interferes with the active transport of calcium ions from the sarcoplasm
back into the sarcoplasmic reticulum would result in _______.
Contraction with no relaxation
Cardiac muscle cells are like skeletal muscle cells in that they both ________.
have striations
Predict the consequences of administration of a compound that blocks the calcium
channels on presynaptic motor neuron terminals.
A. This should ultimately inhibit the release of acetylcholine
B. This should ultimately inhibit the muscle membrane from depolarization
,C. This should ultimately inhibit the release of calcium from the sarcoplasmic reticulum
D. All of the above are correct answers
D. All of the above are correct answers
Predict the consequences of administration of a compound that inhibits
acetylcholinesteras
The muscle will stay contracted
Myofibrils are composed primarily of ________.
Actin and myosin
Binding of ________ to myosin permits cross-bridge _____________ between actin and
myosin.
ATP; detachment
The part of the sarcolemma that invaginates into the interior of skeletal muscle fibers is
the
T tubule system.
Somatic motor neurons release the neurotransmitter _________ at the neuromuscular
junction.
Acetylcholine
The gangster movies call a dead person a stiff, rigor mortis is the proper name. How
does this occur?
Without ATP, muscles remain fixed in their last state of contraction.
T tubules are invaginations of the ________.
, Sarcolemma
One cause of spastic paralysis might be ________.
Inhibition of acetylcholinesterase
Somatic motor neurons release the neurotransmitter _________ at the myoneural
junction.
Acetylcholine
Rigor mortis occurs after death because
Cross-bridges form but can't release.
Given these events:
(1) Acetylcholine is broken down into acetic acid and choline.
(2) Acetylcholine diffuses across the synaptic cleft.
(3) An action potential reaches the terminal branch of the motor neuron.
(4) Acetylcholine combines with a ligand-gated ion channel.
(5) An action potential is produced on the muscle fiber's plasma membrane.
Choose the arrangement that lists the events in the order they occur at a neuromuscular
junction.
3,2,4,5,1
The sites where a chemical substance is transmitted from the presynaptic terminal of an
axon to the postsynaptic membrane of a muscle fiber are called ________.
Neuromuscular junctions
Acetylcholine is released from the presynaptic terminal by the process of _________.
Exocytosis
Correct Answers
What structure runs from Z line to Z line?
Sarcomere
The movement of the troponin-tropomyosin complex requires _______
Ca2+.
The actin filament is a polymer formed from 300 to 400 globular subunits called ______
G-actin.
A myofilament is the _________.
Protein strand composed of actin or myosin
T tubules ________.
Conduct action potentials deep into the muscle cell
A drug that interferes with the active transport of calcium ions from the sarcoplasm
back into the sarcoplasmic reticulum would result in _______.
Contraction with no relaxation
Cardiac muscle cells are like skeletal muscle cells in that they both ________.
have striations
Predict the consequences of administration of a compound that blocks the calcium
channels on presynaptic motor neuron terminals.
A. This should ultimately inhibit the release of acetylcholine
B. This should ultimately inhibit the muscle membrane from depolarization
,C. This should ultimately inhibit the release of calcium from the sarcoplasmic reticulum
D. All of the above are correct answers
D. All of the above are correct answers
Predict the consequences of administration of a compound that inhibits
acetylcholinesteras
The muscle will stay contracted
Myofibrils are composed primarily of ________.
Actin and myosin
Binding of ________ to myosin permits cross-bridge _____________ between actin and
myosin.
ATP; detachment
The part of the sarcolemma that invaginates into the interior of skeletal muscle fibers is
the
T tubule system.
Somatic motor neurons release the neurotransmitter _________ at the neuromuscular
junction.
Acetylcholine
The gangster movies call a dead person a stiff, rigor mortis is the proper name. How
does this occur?
Without ATP, muscles remain fixed in their last state of contraction.
T tubules are invaginations of the ________.
, Sarcolemma
One cause of spastic paralysis might be ________.
Inhibition of acetylcholinesterase
Somatic motor neurons release the neurotransmitter _________ at the myoneural
junction.
Acetylcholine
Rigor mortis occurs after death because
Cross-bridges form but can't release.
Given these events:
(1) Acetylcholine is broken down into acetic acid and choline.
(2) Acetylcholine diffuses across the synaptic cleft.
(3) An action potential reaches the terminal branch of the motor neuron.
(4) Acetylcholine combines with a ligand-gated ion channel.
(5) An action potential is produced on the muscle fiber's plasma membrane.
Choose the arrangement that lists the events in the order they occur at a neuromuscular
junction.
3,2,4,5,1
The sites where a chemical substance is transmitted from the presynaptic terminal of an
axon to the postsynaptic membrane of a muscle fiber are called ________.
Neuromuscular junctions
Acetylcholine is released from the presynaptic terminal by the process of _________.
Exocytosis
