PHGY 214 Chapter 1-5: PHGY214 Textbook Notes

• School: Queen's University
• Department: Physiology
• Course: PHGY 214
• Professor: Funk Colin

Document Summary

Homeostasis: ability of a cell or organism to regulate its internal conditions, usually using feedback systems (usually negative) to respond to changes in external environment. (cid:449)e usuall(cid:455) do(cid:374)"t ha(cid:448)e a set point, but rather a physiological range that we operate most efficiently within (steady state) Homeokinesis: organism will achieve equilibrium in body functions by dynamic processes. Homeostatic state better considered a homeokinetic state: to exist using regular non0random variation. Minimize change to maintain a stable internal environment. Acting in response to distancing from set point internal environment. Regularly initiates small non-random changes to maintain a stable internal environment. Vast number of cells are not in direct contact with the external environment have to mooch off contributions of its other cell type friends. Self-suffi(cid:272)ie(cid:374)t a(cid:373)oe(cid:271)a (cid:448)s. (cid:373)us(cid:272)le (cid:272)ell that (cid:272)a(cid:374)"t get its o(cid:449)(cid:374) (cid:374)utrie(cid:374)ts (cid:271)e(cid:272)ause it"s isolated a(cid:374)d (cid:272)a(cid:374)"t dire(cid:272)tl(cid:455) (cid:373)ake e(cid:454)(cid:272)ha(cid:374)ges (cid:449)ith the e(cid:374)(cid:448)iro(cid:374)(cid:373)e(cid:374)t.