Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
outline 4
Comparative Physiology- Renner Lecture 4
| Term | Definition |
|---|---|
| Diffusion | net movement of molecules from a region of high concentration to a region of low concentration |
| Concentration gradient (C) | the difference in solute concentration between the two compartments |
| net rate of diffusion. | the difference between random movements from one side of a membrane to the other (depends on concentration gradient aka driving force for diffusion) |
| Fick's law of diffusion | Q= deltaC.P.A/mw(solute).x |
| Osmosis | diffusion of water across a semi permeable membrane along its concentration gradient. Presence of solute decreases concentration of water (bc high conc of solute). |
| when does the system reach equilibrium? | when hydrostatic pressure=osmotic pressure |
| hydrostatic pressure (water pressure) | pressure exerted by water. Def from google |
| tonicity | relationship between solute concentrations between compartments |
| how can osmotic pressure be quantified? | by knowing the concentrations of osmotically active particles |
| isotonic | same concentration in the 2 compartments |
| hypotonic | less concentrated relative to the solute. Water concentration is higher. |
| hypertonic | higher number of solute molecules, lower concentration of water. |
| membrane's key features with respect to membrane potential | presence of channels that allow K+ diffusion, minimal diffusion of Na+, membrane is impermeable to protein A- |
| law of electroneutrality | bulk solutions have a balance of +/- charge |
| how does diffusion of K+ occur? squid axon | passive (no ATP) across aqueous pores across membrane formed by protein channels |
| Na+/K+ pump, why is it important? | prevents the loss of concentration gradients of Na+ and K+ when K+ is lost and Na+ is entered. Prevents concentration gradient from diminishing. |
| how does Na+/K+ work? | originally Na+ is favored to go in to the cell because the concentration of it outside the cell is higher. K+ is favored outside the cell because it has a high concentration on the outside. Na+/K+ uses ATP active transport to get 3 Na+ out, 2 K+ in |
| what is Na+/K+ pump composed of? | 2 subunits, catalytic subunit alpha, and glycoprotein beta in a alpha2beta2 arrangement. |
| depolarization, how it affects Na+/K+ pump | making the inside of the cell more positive with respect to the outside. (normally inside is negative). it increases pump rate. |
| accounts for 33% of energy use by cell? | Na+/K+ pump |
Created by:
rusulali97
Popular Physiology sets