Signaling

Long-distance signaling via the bloodstream (e.g., hormones).

The receptor triggers a relay of intracellular molecules, often called a signaling cascade (e.g., using G-proteins or kinases). signaling

Nearby cells are targeted (e.g., neurotransmitters). Long-distance signaling via the bloodstream (e

The signal finally triggers a specific cellular activity, such as gene expression or enzyme activation. Types of Signaling: Autocrine: A cell targets itself. Long-distance signaling via the bloodstream (e.g.