After a skeletal muscle fiber is treated with a membrane permeable drug that speeds up the action of the SR Ca 2-ATPase, how would contraction differ after multiple and frequent action potentials

the twitch would be shorter

Explanation:

In muscle cells, the calcium (Ca2+) pump ATPase membrane transport proteins maintain a low cytosolic Ca2+ concentration in order to promote muscle contraction. Muscle relaxation occurs when the sarcoplasmic reticulum reabsorbs Ca2+ through the Ca2+-ATPase protein, thereby reducing intramuscular Ca2+ levels. In muscle contraction, intracellular Ca2+ levels are raised due to the release of Ca2+ from the sarcoplasmic reticulum (SR) via Ca2+-release channels. In consequence, it is expected that a specific drug that speeds up the action of (Ca2+) pump ATPase protein should shorten the contraction-relaxation cycle by increasing the velocity of muscle relaxation.

answer: c.

explanation:

the dna molecules have a negative charge because of the phosphate groups in their sugar-phosphate backbone, so they start moving through the matrix of the gel towards the positive pole. power is turned on and dna fragments migrate through gel (towards the positive electrode).

explanation: