Phosphorylation cascades are useful signal transduction pathways because they ________.

Protein phosphorylation is commonly involved with which of the following?

A. ligand binding by receptor tyrosine kinases.

B. activation of G protein-coupled receptors.

C. activation of protein kinase molecules.

D. release of Ca2+ from the ER lumen.

Kinases and phosphatases are essential to the cell because they:

What role do phosphatases play in signal transduction pathways?