Create an account
movement of a substance down its concentrated gradient from an area of higher concentration to an area of lower concentration; increases the entropy of the system
movement of a substance through a biological membrane against a concentration gradient
spontaneous passage of molecules and ions, bound to specific carrier proteins, across a biological membrane down their concentration gradients
cellular uptake of materials where the plasma membrane surround and engulfs extracellular materials
openings between two guard els in the epidermis of a plant leaf through which gases are exchanged with the air
toxic nitrogen compound (NH3) excreted by some aquatic organisms; though to have been present Earth's early atmosphere
an organ that regulates water and salt levels, filters water and wastes from the lood, and excretes the end products
functional unit of a kidney consisting of a glomerulus, its associated capsule, and tubule, surrounded by capillaries
vertebrate organism the regulates levels of water and dissolved substances in the body, execreting wastes as urine
an organ that stores urine before it is discharged from the body through the urethra
a ball of capillaries surrounded by a glomerular capsule in the nephron; the site of filtration in the kidneys
takes place in tubules of nephron; cells of tubule reabsorb substances needed by body into the capillaries
cells in tubule wall selectively remove from capillaries material left in blood after filtration or reabsorption and excrete it into filtrate; regulates hormones
a hormone secreted by the adrenal gland; helps regulate sodium and potassium concentrations and water balance
hormone released from the posterior lobe of the pituitary; enhances conservation of water by the kidneys
colorless crystalline compound that is the main nitrogenous breakdown product of protein metabolism in mammals and is excreted in urine
insoluble in H20; requires virtually no H20 for excretion; nontoxic form of nitrogenous waste
microscopic blood vessel penetrating the tissues and consisting of single layer of cells that allows exchange between the blood and tissue fluids
the series of chemical reactions by which a living cell breaks down carbohydrates and obtains energy from them
Please allow access to your computer’s microphone to use Voice Recording.
Having trouble? Click here for help.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!Reload
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
Please upgrade Flash or install Chrome
to use Voice Recording.
For more help, see our troubleshooting page.
Your microphone is muted
For help fixing this issue, see this FAQ.
Star this term
You can study starred terms together