Biological Membranes Flashcards
Active Transport
Transport across the cell membrane that requires the input of cellular energy.
Amphipathic
Molecule that exhibits a difference in polarity between its two ends, resulting in a difference in water solubility
Channel protein
Membrane -spanning proteins that has an inner pore which allows the passage of one or more substances
Concentration gradient
Difference in the concentration of a substance between two regions
Diffusion
Movement of a substance from on area of higher concentration to an area of lower concentration
Facilitated diffusion
Diffusion of a substance with the aid of a membrane protein
Glycoprotein
Protein that has one or more carbohydrates attached
Hydrophobic
Describes a substance or structure repelled by water
Interstitial fluid
Fluid in the small spaces between cells not contained within blood vessels
Osmosis
Diffusion of water molecules down their concentration gradient across a selectively permeable membrane
Passive transport
Form of transport across a cell mentioned that does not require the input of cellular energy
Receptor
Protein molecule that contains a binding site for another specific molecule ( ligand)
Receptor -mediated endocytosis
Endocytosis of ligands attached to membrane - bound receptors
Selective permeability
Feature of any barrier that allows certain substances to cross but excludes others
Sodium - potassium pump
( na+ / K+ ATP - ase)
Membrane - embedded protein pump that uses ATP to move Na+ out of a cell and K+ into the cell
