Cellular Transport

the need for an organism to maintain constant or stable internal conditions

something that triggers a response from an organism to help maintain homeostasis.

Regulates the passage of material into and out of the cell

some molecules can pass directly through while other molecules cannot

a process by which molecules move across a cell membrane but do not require energy from the cell.

a type of passive transport that includes the spreading out of molecules across a cell membrane until they are equally concentrated

a type of passive transport that occurs when some molecules have chemical structures that prevent them from passing directly through a cell membrane, but are able to enter the cell with the aid of transport proteins along a concentration gradient and does not require energy from the cell.

The diffusion of water molecules through a selectively permeable membrane from an area of greater concentration of water to an area of lesser concentration of water. A type of passive transport.

Molecules move against the concentration gradient (from an area of low concentration to an area of high concentration) and require the cell to expend energy.

A form of active transport in which molecules are "pumped" across the cell membrane by transport proteins which requires the use of chemical energy.

Vesicles are used to aid molecules that are too large to pass through a cell membrane (even with the aid of transport proteins) INTO the cell.

Vesicles are used to aid molecules that are too large to pass through a cell membrane (even with the aid of transport proteins) OUT OF the cell.