【Andy】評論

(A) Contact-dependent signaling: Membrane-bound signals bind to receptors on adjacent cells.(B) Endocrine signaling: Cells release signals that travel long distances to affect target cells.(C) Autocrine signaling: Cells release signals that affect themselves and nearby target cells.(D) Paracrine signaling: Cells release signals that affect nearby target cells. A specialized form of paracrine signaling occurs in the nervous systems of animals.Neurotransmitters—molecules made in neurons that transmit a signal to an adjacent cell一are released at the end of a neuron and traverse a narrow space called the synapse.(E) Direct intercellular signaling: Signals pass through a cell junction from the cytosol ofvone cell to adjacent cells.