Plasma Membrane Flashcards
Net movement of dissolved substances across a cell membrane by an energy-requiring process that moves substances against a concentration gradient from a region of lower to higher concentration
Active Transport
An energy-requiring process of bulk transport, in which solids or liquids move into the cell by engulfment
Endocytosis
Form of diffusion involving a specific carrier molecule for the substance
Facilitated Diffusion
A model which proposes that the plasma membrane and other intracellular membranes should be considered as two-dimensional fluids in which proteins are embedded
Fluid Mosaic Model
Substances that dissolves easily in water; also termed polar (Glucose)
Hydrophilic
Substances that tend to be insoluble in water; also termed nonpolar (Carbon Dioxide)
Hydrophobic
Proteins that are embedded in the phospholipid bilayer
Integral Proteins
A specialized process of passive transport in which water molecules move across a partially permeable membrane from an area of high water (low solute) to an area of low water (high solute)
Osmosis
Proteins that are anchored to the exterior of the plasma membrane through bonding with either lipids or integral proteins
Peripheral Proteins
Major type of lipid found in plasma membranes and the main structural component of plasma membranes
Phospholipids
Partially permeable boundary of a cell controlling entry to and exit of substances from a cell
Plasma Membrane
Allows only certain molecules to cross by diffusion
Semi-Permeable
The movement of substances from a region of higher concentration to one of lower concentration of that substance; that is, down its concentration gradient
Simple Diffusion
Proteins that are embedded within and span the plasma membrane, allowing them to have parts exposed to both the intracellular and extracellular environment
Trans-Membrane Proteins
Membrane-bound sacs found within a cell, such as secretory vesicles, which are involved in the export of proteins
Vescicles