Sharks and rays are isotonic to their environments; that is, the concentration of solutes inside their cells is the same as the concentration of solutes in their external environment. How will osmosis affect shark cells?

Phosphorylase kinase

Explanation:

Phosphorylase kinase is a type of regulatory protein kinase which helps in the process of glycogen breakdown.

It sends signals and the process of phosphorylating occurs which then helps in the activation of glycogen phosphorylase and subsequent breakdown of glycogen in the body. This makes phosphorylase kinase the right option.