Biology

The correct answer is: B.signal receptors

Explanation:

A target cell is one that responds to a particular signal molecule, and this response is determined by whether the cell has specific receptors for that signaling molecule. Receptors are proteins that can bind to signaling molecules (e.g., hormones, neurotransmitters), and their binding triggers a cascade of events inside the cell, leading to a response.

A.Phosphorylation cascade: This is a process that often occurs inside target cells after a receptor binds to its signal molecule. It refers to a series of phosphorylation events that relay and amplify the s...