Physiology 3120 Lecture Notes - Lecture 3: Cystic Fibrosis, Dynamic Equilibrium, Membrane Transport

• School: Western University
• Department: Physiology
• Course: Physiology 3120
• Professor: Anita Woods

Document Summary

Osmosis is diffusion of water down its concentration gradient. Important to understand different transport mechanism in the cell because: responsible for ap, spontaneous ap in the heart (heart beats by itself) established by channels, muscle twitch and muscle contraction, when they go wrong ex. All molecules are moving unless they reach absolute 0 (273c: moving because they have a random thermal motion (causes diffusion) Glucose is slower than water because it is a larger molecule. Move down the concentration gradient: high low. Eventually, the molecules will spread out throughout the solvent + reach a chemical/dynamic equilibrium: no concentration gradient = no diffusion, net movement = 0. Diffusion is not efficient over (cid:498)long(cid:499) distances because diffusion is a random movement. The time (t) for diffusion: t=x2/d: x= mean travel distance, d=diffusion coefficient t, e. g. a tenfold increase in diffusion distances requires 100 times longer for the solute molecule to reach dynamic equilibrium.