What is the function of the transverse tubules in a skeletal muscle fiber?
A. They allow action potentials to propagate deep into the center of skeletal muscle cells.
B. They run in parallel with the myofibrils, and have abundant Ca2+-ATPase proteins for pumping Ca2+ back into the sarcoplasmic reticulum.
C. They manufacture and store ATP.
D. They form the Z lines that mark the end of each sarcomere.
E. They store the calcium ions that are the main source of activation for the cross-bridge cycle.
Answer: A
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A) metabolic acidosis B) respiratory acidosis C) metabolic alkalosis D) respiratory alkalosis
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The role of both sexes in fulfilling the function of the reproductive system is to ________
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