Intro, Cells, Fluid, and Electrolyte Balance Flashcards
homeostasis
our cells maintain a stable environment despite external variability
what is the distribution of water within our bodies?
intracellular - 2/3
extracellular 1/3
what is diffusion?
passive movement of particles down the concentration gradient
high to low
what is facilitated diffusion? does this require energy?
channel or carrier-mediated transport
does NOT require energy
what is active transport? what is an example?
ATP powered transport against the concentration gradient
low concentration to high concentration
Na/K pump - 3 Na+ out for 2 K+ in
what is secondary active transport?
concentration gradient of one substance can be used to move another substance across the membrane
-first the cells have to use active transport to create the concentration gradient
is the concentration of sodium higher intracellular or extracellular?
extracellular - 140
is the concentration of chloride higher intracellular or extracellular?
extracellular - 105
is the concentration of potassium higher intracellular or extracellular?
intracellular - 120
is the concentration of calcium higher intracellular or extracellular?
extracellular 2.5
what is osmosis?
diffusion of water across a selectively permeable membrane
-water moves from low solute concentration to high solute concentration
what is osmotic pressure?
the force created when water moves through a membrane from an area with lower solute concentration to an area with higher solute concentration
what is membrane permeability?
hydrophobic molecules can easily pass through the cell membrane while hydrophilic molecules need a channel
what is the cellular response to a hypertonic solution?
more particles in the solution so water moves out of the cell
-cell shrinks!
what is the cellular response to a hypotonic solution?
more particles in the cell, less in the solution so more water moves into the cell
-cell swells!
