Question

The cell membranes in skeletal muscle

A. Are impermeable to ***-soluble substances.

B. Are more permeable to sodium than to potassium ions.

C. Become more permeable to glucose in the presence of insulin.

D. Become less permeable to potassium in the presence of insulin.

E. Show invaginations which connect to a system of intracellular tubules involved in excitation contraction coupling.

Answer 1

A. False The membrane consists largely of lipid.

B. False The reverse is true; sodium ions, being more hydrated than potassium ions, are larger complexes.

C. True Thus glucose is stored as muscle glycogen after a meal.

D. False They become more permeable; injections of insulin and glucose lower the serum potassium level.

E. True These are called the T system of tubules.