AP BIOLOGY

Detailed explanation-1: -Phosphorylation is the addition of a phosphoryl (PO3) group to a molecule. In biological systems, this reaction is vital for the cellular storage and transfer of free energy using energy carrier molecules.

Detailed explanation-2: -Phosphorylation allows cells to accumulate sugars because the phosphate group prevents the molecules from diffusing back across their transporter. Phosphorylation of glucose is a key reaction in sugar metabolism.

Detailed explanation-3: -The phosphorylation of a protein can make it active or inactive. Phosphorylation can either activate a protein (orange) or inactivate it (green). Kinase is an enzyme that phosphorylates proteins. Phosphatase is an enzyme that dephosphorylates proteins, effectively undoing the action of kinase.

Detailed explanation-4: -ATP is able to power cellular processes by transferring a phosphate group to another molecule (a process called phosphorylation). This transfer is carried out by special enzymes that couple the release of energy from ATP to cellular activities that require energy.