AP Biology Chapter 7 Vocabulary
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| 1035928659 | Active transport | The movement of a substance across a biological membrane against its concentration or electrochemical gradient with the help of energy input and specific transport proteins. | 0 | |
| 1035928660 | Amphipathic molecule | A molecule that has both a hydrophilic region and a hydrophobic region. | 1 | |
| 1035928661 | Aquaporin | A transport protein in the plasma membrane of a plant or animal cell that specifically facilitates the diffusion of water across the membrane (osmosis). | 2 | |
| 1035928662 | Concentration gradient | An increase or decrease in the density of a chemical substance in an area. Cells often maintain concentration gradients of ions across their membranes. When a gradient exists, the ions or other chemical substances involved tend to move from where they are more concentrated to where they are less concentrated | 3 | |
| 1035928663 | Cotransport | The coupling of the downhilldiffusion of one substance to the uphilltransport of another against its own concentration gradient. | 4 | |
| 1035928664 | Diffusion | The spontaneous tendency of a substance to move down its concentration gradient from a more concentrated to a less concentrated area | 5 | |
| 1035928665 | Electrochemical gradient | The diffusion gradient of an ion, representing a type of potential energy that accounts for both the concentration difference of the ion across a membrane and its tendency to move relative to the membrane potential. | 6 | |
| 1035928666 | Electrogenic pump | An ion transport protein that generates voltage across a membrane | 7 | |
| 1035928667 | Endocytosis | The cellular uptake of macromolecules and particulate substances by localized regions of the plasma membrane that surround the substance and pinch off to form an intracellular vesicle. | 8 | |
| 1035928668 | Exocytosis | The cellular secretion of macromolecules by the fusion of vesicles with the plasma membrane. | 9 | |
| 1035928669 | Facilitated diffusion | The spontaneous passage of molecules and ions, bound to specific carrier proteins, across a biological membrane down their concentration gradients. | 10 | |
| 1035928670 | Flaccid | Limp. A walled cell is flaccid in surroundings where there is no tendency for water to enter | 11 | |
| 1035928671 | Fluid mosaic model | The currently accepted model of cell membrane structure, which envisions the membrane as a mosaic of individually inserted protein molecules drifting laterally in a fluid bilayer of phospholipids. | 12 | |
| 1035928672 | Gated channel | A protein channel in a cell membrane that opens or closes in response to a particular stimulus. | 13 | |
| 1035928673 | Glycolipid | A lipid covalently attached to a carbohydrate | 14 | |
| 1035928674 | Glycoprotein | A protein covalently attached to a carbohydrate | 15 | |
| 1035928675 | Hypertonic | In comparing two solutions, referring to the one with a greater solute concentration | 16 | |
| 1035928676 | Hypotonic | In comparing two solutions, referring to the one with a lower solute concentration | 17 | |
| 1035928677 | Integral protein | Typically a transmembrane protein with hydrophobic regions that completely spans the hydrophobic interior of the membrane | 18 | |
| 1035928678 | Ion channel | Protein channel in a cell membrane that allows passage of a specific ion down its concentration gradient | 19 | |
| 1035928679 | Isotonic | Having the same solute concentration as another solution. | 20 | |
| 1035928680 | Ligand | A molecule that binds specifically to a receptor site of another molecule. | 21 | |
| 1035928681 | Membrane potential | The charge difference between a cell's cytoplasm and the extracellular fluid, due to the differential distribution of ions. Membrane potential affects the activity of excitable cells and the transmembrane movement of all charged substances. | 22 | |
| 1035928682 | Osmoregulation | The regulation of solute and water concentrations in body fluids by organisms living in hyperosmotic, hypoosmotic, and terrestrial environments | 23 | |
| 1035928683 | Osmosis | The diffusion of water across a selectively permeable membrane | 24 | |
| 1035928684 | Passive transport | The diffusion of a substance across a biological membrane | 25 | |
| 1035928685 | Peripheral protein | A protein appendage loosely bound to the surface of a membrane and not embedded in the lipid bilayer. | 26 | |
| 1035928686 | Phagocytosis | A type of endocytosis involving large, particulate substances, accomplished mainly by macrophages, neutrophils, and dendritic cells. | 27 | |
| 1035928687 | Pinocytosis | A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes | 28 | |
| 1035928688 | Plasmolysis | A phenomenon in walled cells in which the cytoplasm shrivels and the plasma membrane pulls away from the cell wall when the cell loses water to a hypertonic environment | 29 | |
| 1035928689 | Proton pump | An active transport mechanism in cell membranes that uses ATP to force hydrogen ions out of a cell, generating a membrane potential in the process | 30 | |
| 1035928690 | Receptor-mediated endocytosis | The movement of specific molecules into a cell by the inward budding of membranous vesicles containing proteins with receptor sites specific to the molecules being taken in; enables a cell to acquire bulk quantities of specific substances | 31 | |
| 1035928691 | Selective permeability | A property of biological membranes that allows some substances to cross more easily than others. | 32 | |
| 1035928692 | Sodium-potassium pump | A special transport protein in the plasma membrane of animal cells that transports sodium out of the cell and potassium into the cell against their concentration gradients | 33 | |
| 1035928693 | Tonicity | The ability of a solution to cause a cell within it to gain or lose water | 34 | |
| 1035928694 | Transport protein | A transmembrane protein that helps a certain substance or class of closely related substances to cross the membrane | 35 | |
| 1035928695 | Turgid | Very firm. A walled cell becomes turgid if it has a greater solute concentration than its surroundings, resulting in entry of water | 36 |
