After death, muscle fibers run out of ATP and calcium begins to leak from the sarcoplasmic reticulum into the sarcoplasm. This results in a condition known as
A) tetany.
B) treppe.
C) depolarization.
D) rigor mortis.
E) oxygen debt.
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Question 2) Which of the following become connected by myosin cross-bridges during muscle contraction?
A) thin filaments and thick filaments
B) thick filaments and titin filaments
C) z disks and actin filaments
D) thick filaments and t-tubules
E) thin filaments and t-tubules
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Question 3) The narrow space between the synaptic terminal and the muscle fiber is the
A) synaptic knob.
B) motor end plate.
C) motor unit.
D) synaptic cleft.
E) M line.
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Question 4) Each skeletal muscle fiber is controlled by a motor neuron at a single
A) synaptic knob.
B) sarcomere.
C) neuromuscular junction.
D) synaptic cleft.
E) transverse tubule.
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Question 5) In response to action potentials arriving along the transverse tubules, the sarcoplasmic reticulum releases
A) acetylcholine.
B) sodium ions.
C) potassium ions.
D) calcium ions.
E) hydrogen ions.
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Question 6) In the myofibril the thin filament is organized around a rod-like core protein called
A) titin.
B) actin.
C) G actin.
D) nebulin.
E) myosin.
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Question 7) In the myofibril the protein that possesses the active site for myosin heads to bind is called
A) titin.
B) actin.
C) G actin.
D) nebulin.
E) myosin.
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Question 8) In the sarcomere the protein that forms two twisted strands around a central rod-like protein is called
A) titin.
B) actin.
C) G actin.
D) nebulin.
E) myosin.
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Question 9) In the sarcomere which elastic protein attaches the thick filament to the Z line?
A) titin
B) actin
C) G actin
D) nebulin
E) myosin
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Question 10) The region of sarcomere where thin and thick filaments are located is called the
A) I band.
B) A band.
C) Z line.
D) M line.
E) zone of overlap.
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