A chemical signal operating in a paracrine manner is one that
A) is active at a neuronal synapse.
B) affects only the cells that synthesize the paracrine signal.
C) requires transport in the blood before it can act on its target cells.
D) evokes responses from all parts of the vascular system.
E) must move through the air before it reaches its target cells.

Question

Quizplus · Accepted Answer

Paracrine signaling involves chemical signals that act locally, affecting cells in the vicinity of the cell that secretes the signal, rather than requiring transport through the blood or air. This is different from the options provided, making A the correct choice as it is not a characteristic of paracrine signaling.

A Chemical Signal Operating in a Paracrine Manner Is One