Campbell Biology in Focus:Chapter 5: Membrane Transport and Cell Signaling
Adapted from: Urry, L., Cain, M., Wasserman, S., Minorsky, P., Jackson, R., & Reece, J. (2014). Campbell biology in focus. Boston: Pearson Education, Inc. (ISBN# 0321813804)
Terms in this set (50)
The movement of a substance across a cell membrane, with an expenditure of energy, against its concentration or electrochemical gradient; mediated by specific transport proteins.
Having both a hydrophilic region and a hydrophobic region.
A channel protein in the plasma membrane of a plant, animal, or microorganism cell that specifically facilitates osmosis, the diffusion of water across the membrane.
A region along which the density of a chemical substance increases or decreases.
The coupling of the "downhill" diffusion of one substance to the "uphill" transport of another against its own concentration gradient.
Cyclic AMP (cAMP)
A ring-shaped molecule made from ATP that is a common intracellular signaling molecule (second messenger) in eukaryotic cells.
The spontaneous movement of a substance down its concentration gradient, from a region where it is more concentrated to a region where it is less concentrated.
The diffusion gradient of an ion, which is affected by both the concentration difference of the ion across a membrane (a chemical force) and the ion's tendency to move relative to the membrane potential (an electrical force).
An ion transport protein that generates voltage across a membrane.
Cellular uptake of biological molecules and particulate matter via formation of new vesicles from the plasma membrane.
The cellular secretion of biological molecules by the fusion of vesicles containing them with the plasma membrane.
The spontaneous passage of molecules or ions across a biological membrane with the assistance of specific transmembrane transport proteins.
Limp. Lacking in stiffness or firmness, as in a plant cell in surroundings where there is no tendency for water to enter the cell.
Fluid mosaic model
The currently accepted model of cell membrane structure, which envisions the membrane as a mosaic of protein molecules drifting laterally in a fluid bilayer of phospholipids.
A GTP-binding protein that relays signals from a plasma membrane signal receptor, known as a G protein-coupled receptor, to other signal transduction proteins inside the cell.
G-protein coupled receptor
A signal receptor protein in the plasma membrane that responds to the binding of a signaling molecule by activating a G protein. Also called a G protein-linked receptor.
A transmembrane protein channel that opens or closes in response to a particular stimulus.
A lipid with covalently attached carbohydrate(s).
A protein with one or more carbohydrates covalently attached to it.
One of many types of secreted chemicals that are formed in specialized cells, travel in body fluids, and act on specific target cells in other parts of the body, changing the target cells' functioning. Hormones are thus important in long-distance signaling.
Referring to a solution that, when surrounding a cell, will cause the cell to lose water.
Referring to a solution that, when surrounding a cell, will cause the cell to take up water.
Typically a transmembrane protein with hydrophobic regions that extend into and often completely span the hydrophobic interior of the membrane and with hydrophilic regions in contact with the aqueous solution on either side of the membrane (or lining the channel in the case of a channel protein).
A transmembrane protein channel that allows a specific ion to flow across the membrane down its concentration gradient.
Referring to a solution that, when surrounding a cell, has no effect on the passage of water into or out of the cell.
A molecule that binds specifically to another molecule, usually a larger one.
Ligand-gated ion channel
A protein pore in cellular membranes that opens or closes in response to A signaling chemical (its ligand), allowing or blocking the flow of specific ions.
A secreted molecule that influences cells near where it is secreted.
The difference in electrical charge (voltage) across a cell's plasma membrane due to the differential distribution of ions.
Regulation of solute concentrations and water balance by a cell or organism.
The diffusion of water across a selectively permeable membrane.
The diffusion of a substance across a biological membrane with no expenditure of energy.
A protein loosely bound to the surface of a membrane or to part of an integral protein and not embedded in the lipid bilayer.
A type of endocytosis in which large particulate substances are taken up by a cell. It is carried out by some protists and by certain immune cells of animals.
A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes.
A phenomenon in walled cells in which the cytoplasm shrivels and the plasma membrane pulls away from the cell wall; occurs when the cell loses water to a hypertonic environment.
An enzyme that transfers phosphate groups from ATP to a protein, thus phosphorylating the protein.
An enzyme that removes phosphate groups from (dephosphorylates) proteins, often functioning to reverse the effect of a protein kinase.
An active transport protein in a cell membrane that uses ATP to transport hydrogen ions out of a cell against their concentration gradient, generating a membrane potential in the process.
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.
A small, nonprotein, water-soluble molecule or ion that relays a signal to a cell's interior in response to a signaling molecule bound by a signal receptor protein.
A property of biological membranes that allows them to regulate the passage of substances.
Signal transduction pathway
A series of steps linking a mechanical or chemical stimulus to a specific cellular response.
A transport protein in the plasma membrane of animal cells that actively transports sodium out of the cell and potassium into the cell.
The ability of a solution surrounding a cell to cause that cell to gain or lose water.
A transmembrane protein that helps a certain substance or class of closely related substances to cross the membrane.
Swollen or distended, as in plant cells.
A bodily process occuring due to the affect of some foregoing stimulus or agent
of a nerve fiber or impulse originating outside and passing toward the central nervous system
Referring to a secreted molecule that acts on a neighboring cell.