Question

Choose the true statements about skeletal muscle. There may be more than one correct answer.

epinephrine is the most important neurotransmitter for skeletal muscle

blocking all ion channels on the t-tubules would block contraction

ATP must remain high for the muscle to contract and relax

blocking the calcium ATPase would inhibit relaxation

Answer 1

The true statements are.

blocking all ion channels on the t-tubules would block contraction. The ion channels on the T tubules are responsible for the calcium influx to the muscle. If calcium binds to the troponin tropomyosin blockage only the muscle contraction will take place. So if ion channels on t tubules are blocked it affect contraction.

Blocking of calcium ATP ase would inhibit relaxation. Calcium ATP ase is the one that removes calcium out of the cell after contraction. So if it is blocked relaxation will be affected.

About false statements.

epinephrine is the most important neurotransmitter for skeletal muscle. Acetylcholine is the important neurotransmitter for skeletal muscle.

ATP must remain high for the muscle to contract and relax. ATP in the myosin head should be utilised to form ADP and contract. But for relaxation ATP is not necessary.