How does a protein kinase cascade amplify an intracellular signal?
A) It opens gap junctions, allowing the signal to spread to other cells.
B) The activated G protein in the cascade binds and activates a second protein, amplifying the signal.
C) Nitric oxide in the cascade opens gap junctions, allowing protein kinase molecules to move quickly from cell to cell.
D) Second messengers in the cascade create shortcuts that create multiple cascades.
E) Activation of the protein kinase receptors can trigger the activation of many other proteins.

Question

Quizplus · Accepted Answer

Protein kinase cascades involve the phosphorylation and activation of multiple protein kinases in a series. This amplifies the intracellular signal as each activated protein kinase can then go on to activate many other proteins downstream, resulting in a large overall effect. This activation of many proteins from a single upstream signal is what is meant by amplification.

How Does a Protein Kinase Cascade Amplify an Intracellular Signal