KAAP309 Study Guide - Midterm Guide: Pinocytosis, Resting Potential, Motor Protein

• School: University of Delaware
• Department: Kinesiology & Appl Physiology
• Course: KAAP309
• Professor: Rose William

Document Summary

Diffusion: molecules move down or along a concentration gradient, major driving force is kinetic energy of the molecules themselves, speed of diffusion is influenced by molecular size and temperature. Non-polar and lipid soluble substances diffuse directly through the lipid bilayer. Substances include oxygen, co2, and fat soluble vitamins: facilitated diffusion. The transported substance either binds to a protein carrier in the membrane and is ferried across or it moves through water-filled protein channels. Carrier mediated carriers are transmembrane integral proteins that are specific for transporting certain polar molecules or classes of molecules that are too large to pass through membrane channels. The carrier protein changes shape to move the binding site from one face of the membrane to the other. A substance transported by carriers moves down a concentration gradient, just as in simple diffusion. Channel mediated transmembrane proteins that transport substances, usually ions or water, through aqueous channels from one side of the membrane to the other.