chapter 4

autocrine signals

affect the same cell that releases them (tumor cells reproduce uncontrollably bc they self-stimulate cell division by making their own division signals)

paracrine signals

diffuse to and affect nearby cells (e.g. neurotransmitter made by a nerve cell that diffuses to an adjacent cell and stimulates it)

juxtacrine signaling

direct contact between signaling and responding cell (therefore usually involves interaction between signaling molecules bound to the surfaces of the two cells)

hormones

signals that travel long distances in the circulatory/vascular systems to reach receptors

allosteric regulation is...

change in 3D shape as a result of binding ligand