Paracrine?

Paracrine?

• A. Autocrine
• B. Endocrine
• C. Neurotransmitter
• D. Paracrine

Answer: (D)

Paracrine signaling is local communication where a cell releases signaling molecules that diffuse through the surrounding tissue to affect nearby target cells. This short-range action means the molecules don’t travel in the bloodstream and don’t have to reach distant organs. It differs from autocrine signaling, where the cell responds to signals it itself releases; from endocrine signaling, where hormones travel through blood to distant targets; and from neurotransmitter signaling, which uses synapses for rapid, direct communication between neurons or to an adjacent effector cell. An example is a growth factor diffusing to nearby fibroblasts to stimulate their growth, illustrating how the message influences neighboring cells in the local environment.

Paracrine signaling is local communication where a cell releases signaling molecules that diffuse through the surrounding tissue to affect nearby target cells. This short-range action means the molecules don’t travel in the bloodstream and don’t have to reach distant organs. It differs from autocrine signaling, where the cell responds to signals it itself releases; from endocrine signaling, where hormones travel through blood to distant targets; and from neurotransmitter signaling, which uses synapses for rapid, direct communication between neurons or to an adjacent effector cell. An example is a growth factor diffusing to nearby fibroblasts to stimulate their growth, illustrating how the message influences neighboring cells in the local environment.