Question

Muscle contraction is associated with elevated levels of cytosolic calcium. which statement describes a consequence of this increase in calcium?

a. An increased level of calcium is associated with an increase in glycogen breakdown, as calcium is an allosteric activator of phosphorylase b kinase
b. Calcium is a divalent cation, which binds to ATP and reduces electrostatic repulsion between the phosphate. Glycogen is broken down to compensate for the decreased energy available from ATP hydrolysis
c. An increased level of calcium is associated with an increase in glycogen breakdown, as calcium is an allosteric activator of glycogen phosphorylase
d Calcium activates phosphoprotein phosphatase 1, which in turn will stimulate glycogen synthesis by dephosphorylating phosphorylase
e. All the answers are correct.

Answer 1

The consequence of increased cytosolic calcium during muscle contraction is that it acts as an allosteric activator for phosphorylase b kinase, which in turn activates glycogen phosphorylase, leading to the breakdown of glycogen into glucose for energy.

Step-by-step explanation:

The question is about the consequence of increased levels of cytosolic calcium during muscle contraction. Elevated cytosolic calcium leads to several physiological responses in muscle cells. An immediate consequence is associated with glycogen breakdown. Specifically, calcium acts as an allosteric activator of phosphorylase b kinase. This enzyme then activates glycogen phosphorylase, leading to the breakdown of glycogen into glucose which is required for energy during the muscle contraction process.

Therefore, the correct answer is that an increased level of calcium is associated with an increase in glycogen breakdown, as calcium is an allosteric activator of phosphorylase b kinase.