In Paracrine Signaling,the Signaling Molecule

Question

In paracrine signaling,the signaling molecule:
A)acts on cells in close proximity to the secreting cell.
B)acts on target cells far away from the secreting cell.
C)acts on the same cells that secreted the signaling molecule.
D)is carried to the target cells via the circulation.

Accepted Answer

Paracrine signaling involves the release of signaling molecules that act on nearby cells, so the correct answer is that the signaling molecule acts on cells in close proximity to the secreting cell (choice A). The other options are not characteristic of paracrine signaling - choice B describes endocrine signaling, choice C describes autocrine signaling, and choice D describes signaling that involves circulation, which is not characteristic of paracrine signaling.