The formation and release of substance from a cell or structure is called:

a. assimilation

b. excretion

c. secretion

d. synthesis

The formation and release of substance from a cell or structure is called secretion.

Explanation:

There are many biochemical compounds such as hormones, enzymes which are form in specific organ of the body and is then secreted from its source organ to perform their biological functions.

For example Insulin hormone is produced by beta cells of islets of langerhans of pancreas and then releases to the blood stream to regulate the blood sugar level.