intro to physiology and homeostasis Flashcards
what is physiology
study of normal functions of the body and the integrative mechanisms that control them. Cant know what’s wrong unless you know what’s right
control of homeostasis
Physiological control systems are important for maintenance of stable internal environment ‘homeostasis’. Many pharmacological agents act at level of cell membrane to produce therapeutic effect
physiological control
works to achieve a desired response. intrinsic controls and extrinsic
intrinsic controls
local controls that are inherent in an organ.
extrinsic controls
regulatory mechanisms initiated outside an organ, accomplished by nervous or endocrine system.
feedforward
response made in anticipation of a change
feedback
response made after change is detected. types = positive and negative
positive feedback
amplifies an initial response eg contractions during labour
negative feedback
opposes an initial change (main type of physiological control mechanisms)
importance of homeostasis
the body cells and systems maintain homeostasis, many diseases are caused by deficient homeostasis mechanisms
negative feedback control mechanisms
They must be able to sense deviations (sensor), integrate this info (control centre), make appropriate adjustments (effectors).
examples of negative feedback
BP, body temp, blood glucose, blood gases, blood pH
