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| 443315343 | diffusion | when a substance moves from an area of higher concentration to an area of lower concentration; caused by entrapy because nature wants stability | 0 | |
| 443315344 | osmosis | the diffusion of water through a selectively permeable membrane | 1 | |
| 443315345 | dialysis | the diffusion of small solutes through a selectively permeable membrane | 2 | |
| 443315346 | passive transport | diffusion or osmosis; the way a cell gets materials or excretes them by having them go from a high concentration to a low concentration; no ATP is necessary, energy comes from normal collisions; slow over large distances | 3 | |
| 443315347 | active transport | when a cell gets materials or excretes them by using its own energy, usually through ATP; going against natural tendencies | 4 | |
| 443315348 | hypertonic | describes a solution that has a greater concentration of total solute | 5 | |
| 443315349 | hypotonic | describes a solution that has a lesser concentration of total solute | 6 | |
| 443315350 | isotonic | describes solutions that have an equal concentration of total solutes | 7 | |
| 443315351 | turgor pressure | the pressure inside of a cell as a cell pushes itself against the cell wall | 8 | |
| 443315352 | plasmolysis | this happens when a cell shrinks inside its cell wall while the cell wall remains intact; concentration of water decreases, while solute concentration increases | 9 | |
| 443315353 | flaccid | this happens when water moves, but the amount within the cell is constant; no pressure builds | 10 | |
| 443315354 | crenation | this happens when a cell shrinks and shrivels; can result in cell death if severe | 11 | |
| 443315355 | water potential | this states that water will always move from an area with high water potential to an area with low water potential | 12 | |
| 443315356 | solute potential | this measurement has a maximum value of 0; it decreases as the concentration of a solute increases | 13 | |
| 443315357 | pressure potential | this measurement has a minimum value of 0 (when the solution is open to the environment); it increases as pressure increases | 14 | |
| 443315358 | selective permeability | a property of a plasma membrane that allows some substances to cross more easily than others | 15 | |
| 443315359 | amphipathic | molecules are said to be this when it has regions that are both hydrophilic and hydrophobic | 16 | |
| 443315360 | fluid mosaic model | the currently accepted arrangement of membranes; it is a fluid structure with a "mosaic" of various proteins embedded in or attached to a double layer of phospholipids; proposed by Singer and Nicolson in 1972 | 17 | |
| 443315361 | integral proteins | the proteins of a membrane that penetrate the hydrophobic core of the lipid bilayer; hydrophobic regions consist of nonpolar amino acids, while hydrophilic regions are exposed to aqueous solution on either side of membrane | 18 | |
| 443315362 | transmembrane proteins | the proteins of a membrane that span the entire membrane | 19 | |
| 443315363 | peripheral proteins | the proteins of a membrane that are not embedded in the lipid bilayer; they are appendages loosely bound to the surface of the membrane, often exposed to parts of the integral proteins; attached by cytoskeleton on cytoplasmic side, and by fibers of ECM on extracellular side | 20 | |
| 443315364 | transport | the function of membrane proteins that allows travel through a hydrophilic channel, or by transport proteins, which shuttle molecules across the membrane by changing shape with the help of hydrolyzing ATP | 21 | |
| 443315365 | enzymatic activity | the function of membrane proteins that uses the exposure of proteins' active sites to adjacent solutions; metabolic processes progress to help substances pass | 22 | |
| 443315366 | signal transduction | the function of membrane proteins that allow proteins to have binding sites with specific shapes that fit chemical messengers; external messengers may cause a shape change in protein that relays a message to the inside of the cell, usually by binding to a cytoplasmic protein | 23 | |
| 443315367 | cell-cell recognition | the function of membrane proteins in which some glycoproteins serve as ID tags that are recognized by membrane proteins of other cells | 24 | |
| 443315368 | intercellular joining | the function of membrane proteins in which membrane proteins of adjacent cells hook together, as in gap junctions or tight junctions | 25 | |
| 443315369 | attachment to cytoskeleton and extracellular matrix | the function of membrane proteins in which microfilaments bond noncovalently to membrane proteins, maintaining cell shape and protein location; proteins bound to extracellular matrix molecules can coordinate extracellular and intracellular changes | 26 | |
| 443315370 | glycolipids | membrane carbohydrates that are covalently bonded to lipids | 27 | |
| 443315371 | glycoproteins | membrane carbohydrates that are covalently bonded to proteins | 28 | |
| 443315372 | transport protein | a membrane protein that is responsible for moving hydrophilic substances from one side to the other | 29 | |
| 443315373 | channel protein | a membrane protein, specifically a transport protein, that has a hydrophilic channel that certain molecules or atomic ions use as a tunnel | 30 | |
| 443315374 | aquaporin | a membrane protein, specifically a transport protein, that facilitates the passage of water through channel proteins | 31 | |
| 443315375 | carrier protein | a membrane protein, specifically a transport protein, that holds onto molecules and changes their shapes in a way that shuttles them across the membrane | 32 | |
| 443315376 | concentration gradient | the region along which the density of a substance decreases | 33 | |
| 443315377 | up | when a substance diffuses from an area of lower concentration to an area of higher concentration, it is moving ______ its concentration gradient | 34 | |
| 443315378 | down | when a substance diffuses from an area of higher concentration to an area of lower concentration, it is moving ________ its concentration gradient | 35 | |
| 443315379 | tonicity | the ability of a solution to cause a cell to gain or lose water; depends partly on concentration of nonpenetrating solutes relative to inside of cell | 36 | |
| 443315380 | osmoregulation | the control of water balance | 37 | |
| 443315381 | turgid | a cell with a cell wall that has a reasonable amount of pressure but is healthy | 38 | |
| 443315382 | flaccid | a cell with a cell wall that is in an isotonic solution that allows for a steady volume | 39 | |
| 443315383 | facilitated diffusion | passive diffusion that is aided by transport proteins, but that does not require cellular energy | 40 | |
| 443315384 | membrane potential | the voltage of a plasma membrane; ranges from -50 mV to -200 mV; the (-) signifies in which direction the substances move--(-) = outside of cell | 41 | |
| 443315385 | membrane potential | favors the passive transport of cations into the cell and anions out of the cell | 42 | |
| 443315386 | electrochemical gradient | the combination of forces that acts on membrane potential | 43 | |
| 443315387 | nonpolar | when ____________ entities hit the membrane, they dissolve through it and pass through the membrane and into the cell | 44 | |
| 443315388 | ionic | when ____________ entities hit the membrane, they accompany a protein in order to be dissolved, regardless of size | 45 | |
| 443315389 | small nonpolar | when ____________ entities hit the membrane, they pass through the membrane alone | 46 | |
| 443315390 | large polar | when ____________ entities hit the membrane, they are completely blocked from entering | 47 | |
| 443315391 | gated channel | a highly selective tunnel on a plasma membrane that can open or close depending on conformational changes; they are changed due to electrical disturbances, bonding of a specific ligand; allows a substance to diffuse | 48 | |
| 443315392 | electrogenic pump | a transport protein that generates voltage across a membrane, causing a net separation in charge | 49 | |
| 443315393 | proton pump | an electrogenic pump that works largely with H+ ions in plants, fungi, and bacteria | 50 | |
| 443315394 | cotransport | a mechanism through which a single ATP-powered pump that transports a specific solute can indirectly drive the active transport of several other solutes; substances that have been pumped across membrane can do work as they move back across the membrane by diffusion | 51 | |
| 443315395 | exocytosis | occurs when a cell secretes certain biological molecules by the fusion of vesicles with the plasma membrane | 52 | |
| 443315396 | endocytosis | occurs when a cell takes in biological molecules and particulate matter by forming new vesicles from the plasma membrane | 53 | |
| 443315397 | phagocytosis | a type of endocytosis in which the cell engulfs a particle by wrapping pseudopodia around it and packaging it within a membrane-enclosed sac that can be large enough to be considered a vacuole; particle is digested after vacuole fuses with lysosome | 54 | |
| 443315398 | pinocytosis | a type of endocytosis in which the cell "gulps" droplets of fluid into tiny vesicles; molecules dissolved in liquid are necessary for cell; nonspecific in substances it transports | 55 | |
| 443315399 | receptor-mediated | a type of endocytosis in which the cell acquires bulk quantities of specific substances, even though they may not be very concentrated in the extracellular fluid; receptor proteins are already clustered in regions of membrane called coated pits, which are lined on cytoplasmic side by fuzzy layer of coat proteins; when ligands bond to receptors, coated pits form a vesicle that contains ligand molecules | 56 | |
| 443315400 | ligand | any molecule that bonds specifically to a receptor site of another molecule | 57 |
