Term
|
Definition
| Allows some substances to cross it more easily than others. |
|
|
Term
|
Definition
| Has both a hydrophilic region and a hydrophobic region. |
|
|
Term
|
Definition
| The membrane is a fluid structure with a "mosaic" of various proteins embedded in or attached to a double later of phospolipids. |
|
|
Term
|
Definition
| Proteins that penetrate the hydrophobic interior or the lipid bilayer. |
|
|
Term
|
Definition
| Proteins loosely bound to the surface of the membrane. |
|
|
Term
|
Definition
| Membrane carbohydrates (short, branced chains of <15 sugar units) covalently bonded to lipids. |
|
|
Term
|
Definition
| Membrane carbohydrates (short, branced chains of <15 sugar units) covalently bonded to proteins. |
|
|
Term
|
Definition
| Proteins use to transport hydrophilic substances, allowing them to avoid contact with the lipid bilayer. |
|
|
Term
|
Definition
| Channel proteins that allow up to 3 billion water molecules per second to enter, passing single file through its central channel, which fits ten at a time. |
|
|
Term
|
Definition
| The movement of molecules of any substance so that they spread out evenly into the available space. |
|
|
Term
|
Definition
| The region along which the density of a chemical substance increases or decreases. |
|
|
Term
|
Definition
| The diffusion of a substance across a biological membrane; The cell does not have to expend energy. |
|
|
Term
|
Definition
| The diffusion of water across a selectively permeable membrane. |
|
|
Term
|
Definition
| The ability of a surrounding solution to cause a cell to gain or lose water. |
|
|
Term
|
Definition
| No net movement of water. |
|
|
Term
|
Definition
| Cells will gain water and expand. |
|
|
Term
|
Definition
| Cells will lose water and shrivel. |
|
|
Term
|
Definition
| The control of solute concentrations and water balance. |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| As a plant cell shrivels, its plasma membrane pulls away from the wall. |
|
|
Term
|
Definition
| Diffusing passively with the help of transport proteins that span the membrane. |
|
|
Term
|
Definition
| Channel proteins that transport ions (such as gated channels) |
|
|
Term
|
Definition
| Open or close in response to a stimulus |
|
|
Term
|
Definition
| Pumping a solute across a membrane against its gradient (requires work, cell must expend energy) |
|
|
Term
|
Definition
| Exchanged Na+ for K+ across the plasma membrane of animal cells |
|
|
Term
|
Definition
| The voltage across a membrane |
|
|
Term
|
Definition
| The combination f a chemical force (the ion's concentration gradient) and an electrical force (the effect of the membrane potential on the ion's movement) |
|
|
Term
|
Definition
| A transport protein that generates voltage across a membrane |
|
|
Term
|
Definition
| Actively transports protons (hydrogen ions, H+) out of the cell |
|
|
Term
|
Definition
| The coupling of the "downhill" diffusion of one substance to the "uphill" transport of another against its own concentration gradient. |
|
|
Term
|
Definition
| The cell secretes certain biological molecules by the fusion of vesicles with the plasma membrane |
|
|
Term
|
Definition
| The cell takes in biological molecules and particulate matter by forming new vesicles from the plasma membrane |
|
|
Term
|
Definition
| Any molecule that binds specifically to a receptor site on another molecule |
|
|
