chem test 4 matching questions

active transport

The movement of molecules or ions across a cell membrane against their concentration gradient, requiring energy (usually in the form of ATP) and the use of transport proteins.

facilitated transport

The diffusion of ions or small polar molecules across the cell membrane with the assistance of a protein. 

solute

The substance in a solution present in the smaller amount.

solvent

The substance present in the greater amount in a solution, which dissolves the solute. In most biological systems, the solvent is water.

electrolyte

A substance that conducts electricity because it dissociates into ion in aqueous solution.

nonelectrolyte

A substance that does not dissociate into ions in aqueous solution and therefore does not conduct electricity when dissolved in water (e.g., sugar or ethanol).

osmosis

The passage of water across a semipermeable membrane in an effort to equalize the solute concentrations on either side.

concentration

The amount of solute dissolved in a certain amount of solution.

homeostasis

The ability of an organism to regulate its internal environment by adjusting its physiological processes.

amphiprotic

A property which shows the ability to both donate and accept a proton.

isoelectric point

The pH at which an amino acid has a net charge of zero.

buffer

A solution consisting of a weak acid and its conjugate base that resists a change in pH when new acid or base is added.

equilibrium

A state in a reversible reaction where the rate of the forward reaction equals the rate of the reverse reaction, resulting in no net change in the concentrations of reactants and products.

neutralization

The reaction between an acid and a base to for a salt and water.

colloid

A homogeneous mixture containing particles ranging from 1 to 1000 nm in diameter (will not separate upon standing).

suspension

A mixture containing particles greater than 1000 nm in diameter (will separate upon standing).