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22 Cards in this Set
- Front
- Back
Components of the Plasma Membrane |
Phospholipids and Proteins |
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Types of lipids found in Plasma Membrane |
Phospholipids, cholesterol, glycolipids |
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Factors would tend to increase membrane fluidity? |
The presence of cholesterol in the plasma membranes of some animals enables the membrane to stay fluid more easily when cell temperature drops. The following factor would tend to increase membrane fluidity: a greater proportion of unsaturated phospholipids |
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Integral Membrane protein |
Amphipathic - hydrophobic core of the lipid bilayer, often completely spanning the membrane |
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Peripheral Membrane Protein |
Hidrophilic - Are not embedded in the lipid bilayer at all. Instead, they are loosely bound to the surface of the protein, often connected to integral proteins. |
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Glycoproteins Function |
Glycoproteins are proteins that have sugar molecules attached to them Glycoproteins help cells recognize each other |
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Membrane structure results in selective permeability |
Osmosis(special diffusion) - The diffusion of water across a selectively permeable membrane Small hydrophobic molecules pass easily through the membrane |
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Passive transport |
The diffusion of a substance across a biological membrane with no expenditure of energy |
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Diffusion(Passive transport) |
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. |
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Facilitaded Diffusion(Passive transport) |
The spontaneous passage of molecules or ions across a biological membrane with the assistance of specific transmembrane transport proteins. Ex: aquaporins |
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Passive Processes(Passive transport) |
The diffusion of a substance across a biological membrane with no expenditure of energy |
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Active Transport |
The movement of a substance across a cell membrane, with an expenditure of energy, against its concentration or electrochemical gradient. |
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Phagocytosis |
A type of endocytosis in which large particulate substances are taken up by a cell. It is carried out by some protists |
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Pinocytosis |
A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes |
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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 |
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Hypotonic solution |
Solute concentration is less than that inside the cell; cell gains water; cell swell |
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Hypertonic solution |
Solute concentration is greater than that inside the cell; cell loses water; cell shrink |
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Isotonic solution |
Solute concentration is the same as that inside the cell; no net water movement across the plasma membrane |
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Turgor pressure |
The water pressure inside plant cells |
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Tonicity (ability of a surrounding solution to cause a cell to gain or lose water) for animal cell |
Isotonic |
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Tonicity for plants cell (ability of a surrounding solution to cause a cell to gain or lose water) for plant cell |
Hypotonic |
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Membrane potential |
is the voltage across a membrane, the result of the separation of opposite charges. Maintened by electrogenic pumps |