BSC 2011C Lecture Notes - Lecture 24: G Protein–Coupled Receptor, Signal Transduction, Yolk
Document Summary
Animals possess endocrine systems, which is an organ system that coordinates the endocrine response. Hormones: chemical signals that circulate in the blood/hemolymph and communicate regulatory messages. Only specific target cells have receptors to bind to hormones, so only those cells respond to the hormone"s message. Hormones can affect/regulate reproduction, development, energy metabolism, growth, and behavior. Paracrine ( para = one side of): signals act on cells near secreting cells. Autocrine ( auto = self): signals act on secreting cell itself. Endocrine signaling: endocrine cells secrete molecules which diffuse into the bloodstream and. Local regulators: chemical signals act over short distances and reach target cells by diffusion. Synaptic signaling: neurons form specialized junctions (synapses) with target cells. Neuroendocrine signaling: specialized neurosecretory neurons secrete chemical signals. Pheromones: communication between members of the same species by chemical signals that are released into the external environment. They serve roles in defining territories, trail marking, and the attraction of mates.