PHYL 141 Lecture Notes - Lecture 3: Glycolipid, Organelle, Blood Plasma

• School: UH, UH Manoa, UHM
• Department: Physiology
• Course: PHYL 141
• Professor: Rachel Lindsey

Document Summary

Different membrane proteins serve variety of functions: ion channels most are selective, only allow one ion type to pass through. Ex: k+ can flow into or out of cell in potassium ion channel: carriers (transporters) selectively move polar substances or ions from one side of membrane to the other, receptors cellular recognition sites (recognizes specific ligand) Ligand specific molecule that binds to a specific receptor. Ex: abo blood type markers (blood transfusions blood type must be compatible with your own) Electrochemical gradient combined influence of concentration gradient & electrical gradient on movement of a particular ion. Includes simple diffusion, facilitated diffusion, osmosis: active processes cellular energy is used to drive substances against its concentration or electrical gradient, requires cellular energy (atp molecules) Longer diffusion takes: simple diffusion passive process in which substances move freely through lipid bilayer of plasma membranes of cells without help of membrane transport proteins, nonpolar, hydrophobic molecules move across bilayer via simple diffusion.