Cell membrane structure and functions
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| Allows some substances to cross more easily than others | ||
| molecule that has both a hydrophillic region and a hydrophobic region such as a phosopholipid |  | |
| a double layer of phospholipids that makes up plasma membranes |  | |
| Proteins that extend through the phospholipid bilayer. |  | |
| A protein loosely attached to the surface of a membrane | | |
| proteins that have carbohydrates covalently bonded to them | ||
| steroid present in the plasma membranes of animal cells. A large amount of this in a phospholipid bilayer at High Temperatures reduces membrane fluidity, but at Lower Temperature prevents the membrane from solidifying. |  | |
| a difference in the concentration of a substance across a space | ||
| the movement of molecules from an area of higher concentration to an area of lower concentration, so that they spread out evenly reaching equilibrium |  | |
| The diffusion of water across a selectively permeable membrane | ||
| proteins that help to transport substances across cell membranes |  | |
| Channel proteins that help massive amount of water pass through the membrane; a lot in our kidneys | ||
| movement of materials through a cell membrane without using energy | ||
| a solution whose solute concentration equals that inside a cell; the cell will not change |  | |
| the solution with the greater concentration of solutes than that inside the cell; the cell will lose water to its environment--> Cell will shrivel up |  | |
| the solution with the lower concentration of solutes than that inside the cell; water will enter the cell -> Cell will swell and burst |  | |
| The control of water balance | ||
| Very firm (healthy state), especially for plant cells | ||
| As a plant cell shrivels its plasma membrane pulls away from the wall |  | |
| passive transport of ions or polar molecules across a plasma membrane by transport proteins | | |
| transport of a substance through a cell membrane against the concentration gradient; requires energy |  | |
| a carrier protein that uses ATP to actively transport sodium ions out of a cell and potassium ions into the cell |  | |
| process by which a cell releases large amounts of material by vesicles |  | |
| the movement of a substance into a cell by a vesicle | ||
| a type of endocytosis in which microbes are taken in by immune cells of animals (mainly by macrophages) |  | |
| cellular drinking |  | |
| Taking in large amount of specific substances by binding to receptors, which form vesicles and are then taken in by the cell |  | |
| The force required to resist the movement of water by osmosis. Osmotic pressure is a measure of the concentration of a solution. A solution that is highly concentrated has a strong tendency to draw water into itself, so the pressure required to resist that movement would be high. Thus, highly concentrated solutions are said to have high osmotic pressures. |
