Many second messenger systems activate enzymes that transfer a phosphate group from atp to a protein. the phosphorylation of proteins sets off a series of intracellular events that lead to the ultimate cellular response

Many second messenger systems activate kinases, enzymes that transfer a phosphate group from ATP to a protein. The phosphorylation of proteins sets off a series of intracellular events that lead to the ultimate cellular response.

Explanation:

For example, the second messenger cAMP activates the protein kinase A (PKA), which catalyzes the phosphorylation of other proteins.

The second messenger Ca²⁺ forms an active complex with a protein called calmodulin. This complex activates CaM kinases, that phosphorylate a group of target proteins, regulating its activities.

a. seed plant structure. 1. the three main plant organs are roots, stems, and leaves. a fourth kind of tissue, meristematic tissue, is responsible for plant growth. meristematic tissue is the only plant tissue that produces new cells by mitosis. plants can lose water out of their leaves as they exchange gases with the air

explanation:

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.