NROSCI 1250 Study Guide - Midterm Guide: Thyrotropin-Releasing Hormone, Facilitated Diffusion, Adrenal Medulla
Document Summary
40 l of water in body 2/3 located inside cells. Water lows towards side with higher concentraion of solutes (water follows solute) Osmolarity determined when all solutes assumed to be nonpermeable. Tonicity is measured ater solutes are allowed to move. An isotonic cell can only be isosmoic or hyperosmoic, never hypoosmoic bc a normal cell has 300 mosm of nonpermeable solutes inside, so cannot go out. Fick"s law: rate of difusion is proporional to surface area, concentraion gradient, and permeability of membrane. Negaive feedback: (above) set point is monitored, if change in variable occurs, body works to change variable back to original state. Feedforward control: body anicipates a change and adjusts before change occurs. Posiive feedback: not homeostaic process, change in set point results in further change in the same direcion. Open channels: for simple difusion, no energy required, no saturaion occurs. Mediated transport: not all require energy, all can saturate, bind, change conirmaion, unbind.
