1/40
Vocabulary flashcards for Biology Unit 7, covering membrane structure, passive and active transport, and bulk transport.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
Fluid Mosaic Model
Describes the plasma membrane as a mosaic of phospholipids, cholesterol, proteins, glycoproteins, and glycolipids, giving it a fluid character.
Plasma Membrane Composition
Mainly composed of lipids (phospholipids, cholesterol), proteins, and carbohydrates attached to some lipids and proteins.
Glycolipids
Carbohydrates attached to lipids.
Glycoproteins
Carbohydrates attached to proteins.
Phospholipids
Amphiphilic molecules with hydrophilic (polar) heads and hydrophobic (nonpolar) tails.
Integral Proteins
Proteins integrated completely into the membrane structure, with hydrophobic regions interacting with the phospholipid bilayer.
Peripheral Proteins
Proteins found on the exterior or interior surfaces of membranes, attached to integral proteins or phospholipids; may serve as enzymes or structural attachments.
Glycocalyx
Carbohydrate components of glycoproteins and glycolipids on the exterior cell surface, attracting water and important for cell ID.
Selective Permeability
The plasma membrane allows some substances to pass through but not others.
Passive Transport
Naturally occurring movement of substances from high to low concentration, not requiring cell energy.
Concentration Gradient
Range of concentrations of a substance in a space.
Diffusion
Passive process of transport where a substance moves from an area of high concentration to low concentration until equilibrium is reached.
Facilitated Transport
Materials diffuse across the plasma membrane with the help of membrane proteins.
Transport Proteins
Integral proteins involved in facilitated transport, acting as channels or carriers for materials.
Channel Proteins
Proteins with hydrophilic domains and a hydrophilic channel allowing passage through the membrane; can be always open or gated.
Aquaporins
Channel proteins that allow water to pass through the membrane at a high rate.
Carrier Proteins
Proteins that bind a substance and change shape to move the bound molecule across the membrane; specific to one substance.
Osmosis
Movement of free water molecules through a semipermeable membrane down the concentration gradient.
Tonicity
How an extracellular solution can change the volume of a cell by affecting osmosis; correlates with osmolarity.
Osmolarity
Total solute concentration of a solution.
Hypotonic
Extracellular fluid with a lower osmolarity than inside the cell.
Hypertonic
Extracellular fluid with a higher osmolarity than inside the cell.
Isotonic
Extracellular fluid with the same osmolarity as the cell.
Plasmolysis
Cell membrane detaches from cell wall, constricting cytoplasm.
Active Transport
Method of transporting material requiring energy.
Electrochemical Gradient
Gradient produced by combined electrical and chemical forces.
Pumps
Active transport mechanisms working against the gradient, using metabolic energy.
Primary Active Transport
Moves ions across a membrane, creating a charge difference; directly dependent on ATP.
Secondary Active Transport
Movement of material due to the electrochemical gradient established by primary active transport; doesn't directly require ATP.
Uniporter
Carrier protein that transports one specific ion or molecule.
Symporter
Carrier protein that transports two different ions or molecules in the same direction.
Antiporter
Carrier protein that transports two different ions or molecules in opposite directions.
Co-transport
Use of kinetic energy of Na ions to bring other compounds into the cell against their concentration gradient.
Endocytosis
Active transport that moves particles (large molecules, cell parts, whole cells) into a cell; plasma membrane invaginates to form a vesicle.
Phagocytosis
"Cell eating," large particles are taken in by a cell after clathrin coats part of the inward surface of plasma membrane.
Clathrin
Protein that stabilizes a section of the plasma membrane during phagocytosis.
Pinocytosis
"Cell drinking," takes in molecules (like water) from extracellular fluid.
Potocytosis
Variation of pinocytosis using caveolin as a coating protein.
Caveolin
Coating protein involved in potocytosis.
Receptor-mediated Endocytosis
Endocytosis using specific binding proteins in the plasma membrane for specific molecules, and clathrin-coated pits.
Exocytosis
Reverse process of endocytosis; expels material from the cell into extracellular fluid.