BIOSC-101 Lecture Notes - Lecture 16: Electric Potential, Carbonic Anhydrase, Aquaporin

• School: Diablo Valley College
• Department: Biological Science
• Course: BIOSC-101
• Professor: wyler

Document Summary

Water moves across a membrane from low to high solute concentration through. Cells must balance osmotic conditions to maintain homeostasis osmosis. Plant cells maintain a high solute cytosol concentration (turgor pressure) Aquaporin: channel that allows water to flow in or out of the cell. Tetramer each with 6 membrane spanning a-helices. The pore is slightly larger than one water molecule. The inside forms one h-bond with water to pass it through. There are four classes of atp powered pumps phosphorylation phosphorylation of an a-subunit. P- class: only transport ions against the concentration gradient. V- class: only transport ions (mostly h+) against the concentration gradient. F- class only transports ions (mostly h+) with the concentration gradient. Examples: cells maintains cytosol ph of 7. 2 with high k+, low na+, low. Transport small molecules (amino acids, lipids, peptides, sugars) phosphorylation. These differences are used to drive call processes. Example: neurons use na+/k+ pump to generate action potentials.