Campbell Biology 9th Edition - Chapter 7 Flashcards

Membrane Structure and Function

1430937063	amphipathic	molecule that has both a hydrophilic region and a hydrophobic region such as a phosopholipid	0
1430937064	fluid mosaic model	structural model of the plasma membrane where molecules are free to move sideways within a lipid bilayer	1
1430937065	selective permeability	A property of biological membranes that allows them to regulate the passage of substances.	2
1430937066	integral protein	Typically transmembrane proteins with hydrophobic regions that completely span the hydrophobic interior of the membrane.	3
1430937067	peripheral proteins	protein appendages loosely bound to the surface of the membrane and not embedded in the lipid bilayer.	4
1430937068	glycolipid	membrane carbohydrates that are covalently bonded to lipids	5
1430937069	glycoprotein	a protein with one or more carbohydrates covalently attached to it.	6
1430937070	transport protein	A transmembrane protein that helps a certain substance or class of closely related substances to cross the membrane.	7
1430937071	aquaporin	a transport protein in the plasma membrane of a plant or animal cell that specifically facilitates the diffusion of water across the membrane	8
1430937072	diffusion	process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated	9
1430937073	concentration gradient	a difference in the concentration of a substance across a distance	10
1430937074	passive transport	The movement of materials through a cell membrane without using energy	11
1430937075	osmosis	diffusion of water through a selectively permeable membrane	12
1430937076	tonicity	The ability of a solution to cause a cell within it to gain or lose water	13
1430937077	isotonic	when the concentration of two solutions is the same	14
1430937078	hypotonic	having a lower concentration of solute than another solution	15
1430937079	hypertonic	solution that has a higher concentration of dissolved particles compared with another solution	16
1430937080	osmoregulation	The control of water balance in organisms living in hypertonic, hypotonic, or terrestrial environments.	17
1430937081	plasmolysis	collapse of a walled cell's cytoplasm due to a lack of water	18
1430937082	facilitated diffusion	movement of specific molecules across cell membranes through protein channels	19
1430937083	ion channel	a transmembrane protein channel that allows a specific ion to flow across the membrane down its concentration gradient	20
1430937084	gated channel	a transmembrane protein channel that opens or closes in response to a particular stimulus	21
1430937085	phagocytosis	the process by which a cell engulfs foreign substances or other cells	22
1430937086	pinocytosis	process by which a cell takes in liquid from the surrounding environment	23
1430937087	Receptor mediated endocytosis	allows the cell to acquire bulk quantities of specific substrates by receptors to which substrates attach which are then engulfed by the cell	24
1430937088	endocytosis	process by which a cell takes material into the cell by infolding of the cell membrane	25
1430937089	exocytosis	process by which a cell releases large amounts of material	26
1430937090	ligand	A molecule that binds specifically to a receptor site of another molecule.	27
1430937091	electrogenic pump	An ion transport protein that generates voltage across a membrane	28
1430937092	proton pump	An active transport mechanism in cell membranes that uses ATP to force hydrogen ions out of a cell, generating a membrane potential in the process	29
1430937093	electrochemical gradient	The diffusion gradient of an ion, representing a type of potential energy that accounts for both the concentration difference of the ion across a membrane and its tendency to move relative to the membrane potential.	30
1430937094	cotransport	a single ATP powered pump that transports one solute can indirectly drive the active transport of several other solutes in this mechanism as the solute that has been actively transported diffuses back passively through a transport protein its movement can be coupled with the active transport of another substance against its concentration gradient	31
1430937095	membrane potential	The charge difference between a cell's cytoplasm and the extracellular fluid, due to the differential distribution of ions. Membrane potential affects the activity of excitable cells and the transmembrane movement of all charged substances.	32
1430937096	Na K Pump	Active transporter that moves three Na+ out of a cell and two K+ into the cell against their respective concentration gradients.	33
1430937097	active transport	energy-requiring process that moves material across a cell membrane against a concentration difference	34