PHYSL212 Study Guide - Electrochemical Gradient, Membrane Potential, Exocytosis

• School: University of Alberta
• Department: Physiology
• Course: PHYSL212
• Professor: Saswati Das

Document Summary

Endocytosis (cid:0) uptake: phagocytosis: cell eating receptors, pinocytosis: cell drinking no receptors. Receptor mediated endocytosis: highly selective, clathrin role in vesicle formation. Selective viruses such as hiv take advantage of receptor-mediated endocytosis to import themselves into the immune system (into white blood cells) Driving forces for non-vesicular transport: chemical driving force: concentration gradient, electrical driving force: ion related repulsion and attraction forces, most cells in the body have a negative membrane potential, electrochemical driving force: Electrochemical driving force (cid:0) sum of electrical and chemical. Equilibrium potential (cid:0) membrane potential at which the electrical driving force is equal and opposite to the chemical driving force. Passive movement of molecules through a biological membrane"s lipid bilayer. Net flux: permeability (p) x surface area (sa) x concentration gradient (c1-c2) Facilitated transport concentration dependent, no atp. Active transport 2 types (primary/secondary) atp (secondary does not directly use atp) Pore number of channels = flux = saturation due to limited number of channels.