AP Biology (Campbell) Chapter 7 Flashcards

7510725737	plasma membrane	a microscopic membrane of lipids and proteins that form the external boundary of the cytoplasm of a cell or encloses a vacuole and that regulates the passage of molecules in and out of the cytoplasm.	0
7510725738	selectively permeable	A membrane that allows certain molecules or ions to pass through more easily than other, by means of active or passive transport.	1
7510725739	phospholipids	consist of a glycerol molecule, two fatty acids, and a phosphate group that is modified by an alcohol. The phosphate group is the negatively-charged polar head, which is hydrophilic. The fatty acid chains are the uncharged, nonpolar tails, which are hydrophobic.	2
7510725740	lipids and proteins	primary macromolecules found in membranes	3
7510725741	fluid mosaic model	The fluid mosaic model explains various observations regarding the structure of functional cell membranes. In this model, the cell membrane as a two-dimensional liquid that restricts the lateral diffusion of membrane components.	4
7510725742	transmembrane proteins	the integral protein completely spans the membrane.	5
7510725743	integral proteins	proteins that penetrate the hydrophobic interior of the lipid bilayer. C-C chemokine receptor type 5 is such a protein found in white blood cells.	6
7510725744	peripheral proteins	proteins that are not embedded in the lipid bilayer (Peripheral = of, relating to, or situated on the edge.	7
7510725745	cell-cell recognition	is one of the ways by which cells communicate with one another. It is possible through specific cellular adhesion molecules on the surface of the cell.	8
7510725746	transport proteins	proteins that span the plasma membrane and aid in passive or active transport	9
7510725747	channel proteins	transport proteins that certain molecules or ions use as a tunnel cross the plasma membrane.	10
7510725748	aquaporins	channel proteins that facilitate the passage of water. The interior Amino Acids are polar and thefore allow a polar channel for the water molecules to pass the nonpolar region of the plasma membrane.	11
7510725749	carrier proteins	transport proteins that bind to molecules and change shape to shuttle them across the membrane.	12
7510725750	diffusion	the process by which molecules spread from areas of high concentration to areas of low concentration.	13
7510725751	concentration gradient	is the process of particles, which are sometimes called solutes, moving through a solution or gas from an area with a higher number of particles to an area with a lower number of particles. The areas are typically separated by a membrane.	14
7510725752	passive transport	transport that requires no energy input from the cell (ATP) for transport to occur. Simple diffusion and channel proteins like Aquaporins are examples of passive transport.	15
7510725753	osmosis	a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane.	16
7510725754	tonicity	The ability of an extracellular solution to make water move into or out of a cell by osmosis is known as its tonicity. A solution's tonicity is related to its osmolarity, which is the total concentration of all solutes in the solution.	17
7510725755	isotonic	Water enters and leaves the cell at the same rate, so no net change in the osmotic pressere. The cell stays the same.	18
7510725756	hypertonic	when the cell is immersed in a hypertonic solution where it loses water to its environment, shrivels and probably dies.	19
7510725757	hypotonic	when a cell is immersed in a Hypotonic solution, water enters the cell faster than it leaves, it swells and lyses (explodes) like an overfilled water balloon.	20
7510725758	osmoregulation	the maintenance of constant osmotic pressure in the fluids of an organism by the control of water and salt concentrations.	21
7510725759	Paramecium spp.	a single-celled organism that lives in pond water. It has a contractile vacuole that pumps out excess water from the organism.	22
7510725760	turgid	when the plant cell is very firm, which is a healthy state for most plant cells.	23
7510725761	flaccid	limp, not firm or strong (If a plant is not watered enough, its leaves become droopy and flaccid.)	24
7510725762	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.	25
7510725763	facilitated diffusion	the passive movement of molecules down their concentration gradient with the help of transport proteins.	26
7510725764	ion channels (gated channels)	Channels that open or close depending on the presence or abscence of an electrical, chemical, or physical stimulus.	27
7510725765	active transport	transport that requires the cell to expend metabolic energy and enables a cell to maintain internal concentrations of small molecules. Requires energy.	28
7510725766	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.	29
7510725767	proton pumps	A proton pump is an integral membrane protein that is capable of moving protons across a biological membrane. Mechanisms are based on conformational changes of the protein structure.	30
7510725768	exocytosis	a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.	31
7510725769	endocytosis	the taking in of matter by a living cell by invagination of its membrane to form a vacuole.	32
7510725770	phagocytosis	the ingestion of bacteria or other material by cells such as amoebas. "Cell Eating"	33
7510725771	pinocytosis	the ingestion of liquid into a cell by the budding of small vesicles from the cell membrane. "Cell Drinking"	34
7510725772	receptor-mediated endocytosis	is a process by which cells absorb metabolites, hormones, other proteins - and in some cases viruses - (endocytosis) by the inward budding of the plasma membrane vesicles containing proteins with receptor sites specific to the molecules being taken in.	35
7510725773	lipoproteins	any of a group of soluble proteins that combine with and transport fat or other lipids in the blood plasma. Cholestorol is the kind you hear the most about since high levlse of LDL cholesterol are linked to cardiovascular disease.	36