Cell Membrane & Transport

Maintaining a stable internal environment

thin, flexible barrier around a cell; regulates what enters and leaves the cell

a special organic molecule with a polar head and nonpolar tails.

the structure of the cell membrane

a property of cell membranes that allows some substances to pass through, while others cannot

helps move substances across a cell membrane

Transmits messages in and out of cells. They allow communication between cells.

identify the cell to other cells

difference in the amount of a substance from one location to another

when there is an equal amount of molecules on each side of a membrane

Describes the cell membrane as a tapestry of several types of molecules (phospholipids, cholesterols, and proteins) that are constantly moving.

A lipid that forms an essential component of cell membranes that helps keep the phospholipids spaced evenly.

Requires NO energy, Movement of molecules from high to low concentration, Moves with the concentration gradient

Requires energy, Movement of molecules from low to high concentration, Moves against the concentration gradient

Movement of molecules from an area of higher concentration to an area of lower concentration.