AP Biology Chapter 7 Flashcards

15225344304	plasma membrane	seperates the living cell from its surroundings. Contros traffic in and out of the cell. Is selectively permeable.	0
15225344305	selectively permeable	allows some substances to cross more easily than others.	1
15225344306	phospholipids	most abundant lipids	2
15225344307	lipids and proteins	main macromolecules in membranes	3
15225344308	amphipatic molecules	have hydrophobic and hydrophilic regions	4
15225344309	fluid mosaic model	The arrangement of phospholipids and proteins in biological membranes is described by the...	5
15225344310	freeze-fracture	preparation technique that splits a membrane along the middle of the phospholipid bilayer	6
15225344311	transmembrane proteins	the integral protein completely spans the membrane as...	7
15225344312	integral proteins	proteins that penetrate the hydrophobic interior of the lipid bilayer	8
15225344313	peripheral proteins	proteins that are not embedded in the lipid bilayer	9
15225344314	cell-cell recognition	the ability of a cell to disitnguish one type of neighboring cell from another.	10
15225344315	supramolecular structure	many molecules ordered into a higher level of organization with emergent properties than those of the individual molecules.	11
15225344316	transport proteins	proteins that span the membrane.	12
15225344317	channel proteins	transport proteins that have a hydrophilic channel that certain molecules or ions use as a tunnel though the membrane.	13
15225344318	aquaporins	channel proteins that facilitate the passage of water	14
15225344319	carrier proteins	transport proteins that bind to molecules and change shape to shuttle them across the membrane.	15
15225344320	diffusion	movement of molecules of any substance to spread out in available space	16
15225344321	concentration gradient	the region along which the density of a chemical substance increases or decreases.	17
15225344322	passive transport	transport that requires no energy from the cell to make it happen	18
15225344323	osmosis	the diffusion of water across a selectively permeable membrane	19
15225344324	tonicity	the ability of a surrounding solution to cause a cell to gain or lose water.	20
15225344325	isotonic (animal cell)	if a cell with no cell wall is immersed in an enviroment where there is no net movement of water across the plasma membrane. Stays the same.	21
15225344326	hypertonic (animal cell)	when the cell is immersed in a solution where it loses water to its environment, shrivels and probably dies.	22
15225344327	hypotonic (animal cell)	when a cell is immersed in a solution, water enters the cell faster than it leaves, it swells and lyses (explodes) like an overfilled water balloon.	23
15225344328	osmoregulation	the control of water balance	24
15225344329	Paramecium	is a protist that is hypertonic to the pond water in which it lives.	25
15225344330	turgid	when the plant cell is very firm, which is a healthy state for most plant cells.	26
15225344331	hypotonic (plant cell)	when a plant cell is immersed in a __________ solution the cell contents swell due to osmosis until the elastic cell wall exerts turgor pressure on the cell that opposes further water outake.	27
15225344332	isotonic (plant cell)	when a plant cell is immersed in a _______ solution; there is no net movement. The cell becomes flaccid and the plant may wilt.	28
15225344333	flaccid	limp, not firm or strong (If a plant is not watered enough, its leaves become droopy and flaccid.)	29
15225344334	hypertonic (plant cells)	the plant cell loses water, its volume shrinks. The plasma membrane pulls away from the wall, this is plasmolysis. It is lethal to the cell.	30
15225344335	plasmolysis	This happens when a cell shrinks inside its cell wall while the cell wall remains intact. The plasma membrane pulls away from the wall.	31
15225344336	facilitated diffusion	the passive movement of molecules down their concentration gradient with the help of transport proteins.	32
15225344337	ion channels (gated channels)	Channels that open or close depending on the presence or abscence of an electrical, chemical, or physical stimulus.	33
15225344338	cystinuria	human disease characterized by the absence of a carrier protein that transports cysteine and other amino acids across the membranes of kidney cells.	34
15225344339	active transport	transport that requires the cell to expend metabolic energy and enables a cell to maintain internal concentrations of small molecules. Requires energy.	35
15225344340	ATP	supplies energy for most active transport	36
15225344341	sodium-potassium pump	transport protein that, translocating the bound solute across the membrane. Exchanges sodium ions (Na) for potassium ions (K) across the plasma membrane of animal cells.	37
15225344342	membrane potential	voltage across a membrane. Ranges form -50 to -200 millivolts. The inside of the cell is negative to the outside.	38
15225344343	electrochemical gradient	2 combined forces drive the diffusion of ions across the membrane.	39
15225344344	electrogenic pumps	special transport proteins that generate the voltage gradient across a membrane. Ex. sodium potassium pump and proton pumps.	40
15225344345	sodium-potassium pump	major electrogenic pump in animals. Restores the electrochemical gradient by setting up a concentration gradient. It pumps 2 K ions for every 3 Na ions that it moves out, it generates a voltage.	41
15225344346	proton pumps	the major electrogenic pump. Transports protons out of the cell and transfers positive charge form the cytoplasm to the extracellular solution.	42
15225344347	cotransport	single ATP-powered pump that transports a specific solute can indirectly drive the active transport of several other solutes in a mechanism.	43
15225344348	exocytosis	transport vesicle budded from the Golgi apparatus is moved by the cytoskeleton to the plasma membrane. When the 2 membranes come in contact, the bilayers fuse spill the contents.	44
15225344349	endocytosis	a cell brings in biological molecules and particulate matter by forming new vesicles from the plasma membrane. 3 types: phagocytosis, pinocytosis and receptor-mediated endocytosis.	45
15225344350	phagocytosis	a cell engulfs a particle in a vacuole. The vacuole fuses with a lysosome to digest the particle.	46
15225344351	pinocytosis	molecules are taken up when extracellular fluid is "gulped" into tiny vesicles.	47
15225344352	receptor-mediated endocytosis	endocytosis that enables a cell to acquire bulk quantities of specific materials that may be in low concentrations in the environment.	48
15225344353	lipoproteins	complexes of proteins and lipids. Cholesterol travels in low density _______	49
15225344354	ligands	A molecule that binds specifically to a receptor site of another molecule.	50
15225344355	dialysis	movement of particles in a solution through permeable membranes. The diffusion of small solutes through a selectively permeable membrane.	51