BIOL-2126EL Lecture Notes - Lecture 16: Paracrine Signalling, Autocrine Signalling, Hydrophile
16 Dec 2015
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Document Summary
Each cell responds to a limited set of extracellular signals, depending on its history and. Some hormones cross the plasma membrane and bind to intracellular receptors: extracellular molecules fall into two classes, molecules that are too large / hydrophilic to cross membrane rely on cell surface receptors to relay message across the membrane. Some dissolved gases cross the plasma membrane and activate intracellular enzymes. Ion-channel-coupled receptors convert chemical signals into electrical ones: rapid transmission of signals across synapses in the nervous system, neurotransmitter binds receptor alters its conformation to open an ion channel in the plasma membrane. G-protein-coupled receptors: each is made of a single polypeptide chain that threads back and forth across the lipid bilayer seven times. Some bacterial toxins cause disease by altering the activity of g proteins: can inhibit gi which does not allow the g protein to be turned of.
