Can a contracted muscle relax without ATP?

Can a contracted muscle relax without ATP?

Calcium is then pumped back into the sarcoplasmic reticulum breaking the link between actin and myosin. Actin and myosin return to their unbound state causing the muscle to relax. Alternatively relaxation (failure) will also occur when ATP is no longer available

What happens when there is no ATP for muscle contraction?

A muscle also can stop contracting when it runs out of ATP and becomes fatigued ([link]). Ca++ ions are pumped back into the SR, which causes the tropomyosin to reshield the binding sites on the actin strands. A muscle may also stop contracting when it runs out of ATP and becomes fatigued.

Does ATP cause muscle relaxation?

ATP is also used to lower myoplasmic calcium levels during muscle relaxation. Thus, muscle contractility is intimately linked to the proper control of sarcomeric Ca2+ delivery and (or) removal and ATP generation and (or) utilization.

Why do we need ATP for the muscle to relax?

When actin handholds are exposed by calcium binding to the actin microfilament, myosin spontaneously grabs an actin handhold and pulls once. In order for it to release that handhold and pull again, ATP must provide energy for the release motion. Thus, ATP is consumed at a high rate by contracting muscles.

Is ATP required for muscle relaxation?

ATP is required for both muscle contraction and muscle relaxation.

Can a contracted muscle relax in the absence of ATP?

Muscle contraction does not occur without sufficient amounts of ATP. The amount of ATP stored in muscle is very low, only sufficient to power a few seconds worth of contractions. As it is broken down, ATP must therefore be regenerated and replaced quickly to allow for sustained contraction.

What causes a muscle to relax after it has contracted?

A muscle also can stop contracting when it runs out of ATP and becomes fatigued ([link]). Ca++ ions are pumped back into the SR, which causes the tropomyosin to reshield the binding sites on the actin strands. A muscle may also stop contracting when it runs out of ATP and becomes fatigued.

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