ANP 1105 Lecture Notes - Lecture 6: Arrector Pili Muscle, Preganglionic Nerve Fibers, Postganglionic Nerve Fibers

• School: University of Ottawa
• Department: Anatomy and Physiology
• Course: ANP 1105
• Professor: William Staines

Document Summary

A system in which variables are regulated so that internal conditions remain stable and relatively constant. Not unchanging - rather a dynamic state of equilibrium involving many systems: Heart activity/blood pressure monitored & adjusted as needed. 3 essential characteristics: receptor: senses change (stimulus) & sends info (afferent pathway) to: Control centre: determines set point for variable maintenance; analyzes info & determines correct response. Effector: provides means for response (output along efferent pathway) Feedback (negative/positive) allows for regulation within a range/enhanced response. 1 hormone regulating a process: negative feedback secretion. Process regulated in opposite directions by 2 different hormones eg: blood glucose. Goal of negative feedback: prevent sudden, severe changes. Positive feedback mechanisms response of mechanism enhances original stimulus output is further stimulated. Change occurs in same direction as original response. Most disease seen as a disturbance of homeostasis = homeostatic imbalance.