| A | B |
| Active Transport | The transport of molecules across a membrane and against their natural flow; mediated by carrier proteins and requiring outside energy. |
| Carrier Protein | A protein responsible for mediating the active transport of molecules from one side of the lipid bilayer to the other. Transport is carried out by a conformational change that occurs within the protein that forms an opening for specific molecules to pass through. |
| Channel Protein | A protein responsible for mediating the passive transport of molecules to pass through. |
| Diffusion | The transport process in which molecules naturally travel from an area of higher concentration to an area of lower concentration. |
| Glycocalyx | A layer of carbohydrates that coats the exterior of higher-ordered cells. Functions in protecting the cell from damage. |
| hydrophilic | A polar molecule that selectively associates itself with water through hydrogen bonds. |
| hydrophobic | A nonpolar molecule that does not readily associate with water through hydrogen bonds. |
| Ionophore | A class of membrane transport proteins. Small, hydrophobic molecules that increase membrane permeability to certain ions |
| lipid bound protein | Membrane proteins that are located entirely within the lipid bilayer, having no part touching either the inside or outside of the cell. |
| lipid bilayer | A thin double layer of phospholipid molecules. Provides the structure of a cell membrane. Structure is a result of hydrophobic and hydrophilic forces. |
| multipass protein | Transmembrane proteins that cross the lipid bilayer more than one time. |
| osmosis | The process by which water naturally travels from an area of high concentration to one of lower concentration. |
| Passive Transport | Transport mediated by channel proteins. The movement of molecules across a membrane according to the natural flow. |
| Peripheral Protein | A membrane protein that can be easily removed from the lipid bilayer. |
| Single Pass Protein | A transmembrane protein that only crosses the lipid bilayer one time. |
| Transmembrane Protein | A membrane protein that spans the lipid bilayer having portions in contact with both the inside and outside of the cell. Area within the lipid bilayer forms an alpha-helix. |