Ap Biology Vocab

a type of weak chemical bond formed when the slightly positive hydrogen atom of one hydrogen of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule.

the binding together of like molecules, often by hydrogen bonds

the attraction between different kinds of molecules

a measure of how difficult it is to stretch or break the surface of the liquid

having an affinity for water

a long molecule consisting of many similar or identical monomers linked together

the subunit that serves as a building block for polymers

a chemical process that lyses, or splits, molecules by the addition of water

a chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule

a sugar (monosaccharide) or one of its dimers (disaccharide) or polymers (polysaccharides)

any group of a large biological molecules, including fats, phospholipids, and steriods that mix poorly, if at all, with water

a biologically functional biomolecule consisting of one or more polypeptides folded and coiled into a specific, three- dementional structure

a process in which a protein loses its native shape due to the disruption of weak chemical bonds and interactions, thereby becoming biologically inactive

the totality of an organism's chemical reactions, consisting of catabolic and anabolic pathways, which manage the material and energy resources of the organism

a metabolic pathway that releases energy by breaking down complex molecules into simpler molecules

a metabolic pathway that consumes energy to synthesize a complex molecule from its simpler molecules

an organism that obtains organic food molecules without eating other organisms or substances derived from other organisms. they use energy from the sun or from oxidation of inorganic substances to make organic molecules from inorganic ones

an organism that obtains organic food molecules by eating other organisms or substances derived from them

the complete or partial loss of electrons from a substance involved in a redox reaction

the complete or partial loss of electrons from a substance involved in a redox reaction

a spontaneous chemical reaction, in which there is a net release of free energy

a non-spontaneous chemical reaction, in which free energy is absorbed from the surroundings

An adenine-containing nucleotide triphosphate that releases free energy when its phosphate bonds are hydrolyzed. this energy is used to drive endergonic reactions in a cell.

a chemical agent that selectively increases the rate of a reaction without being consumed by the reaction.

a macromolecule serving as a catalyst. Most are proteins

the amount of energy that reactants must absorb before a chemical will start

the reactant which an enzyme works

the specific region of an enzyme that binds the substrate and that forms the pocket in which catalysis occurs

a substance that reduces the activity of an enzyme by entering the active site in place of the substrate, whose structure mimics it

a substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing the enzyme's shape so that the active site no longer effectively catalyzes the conversation of substrate to product

the binding of a regulatory molecule to a protein at one site that effects the function of the protein at a different site

a method of metabolic control in which the end product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway

a type of well lacking membrane-enclosed organelles

a type of cell with membrane-enclosed organelles

the membrane at the boundary of every cell that acts as a selective barrier, regulating the cell's chemical composition

a property of biological membranes that allow them to regulate the passage of substances across them

the currently accepted model of cell membrane structure, which invisions the membrane as a mosaic of protein molecules drifting laterally in a fluid bilayer of phospholipids

a transmembrane protein with hydrophobic regions that extend into and often completely span the hydrophobic interior of the membrane and with aqueous solution on one or both sides of the membrane (or living the channel in the case of channel proteins)

a transmembrane protein that helps a certain substance or class of closely related substances to cross the membrane

the spontaneous movement of a substance down its concentration or electrochemical gradient, from a region where it is more concentrated to a region where it is less concentrated

a region along which the density of a chemical substance increases or decreases

referring to a solution that when around a cell, will cause the cell to lose water

referring to a solution that, when around a cell will cause the cell to take up water

the diffusion of a substance across a biological membrane with no expenditure of energy

referring to a solution that, when surrounding a cell, causes no net movement of water into or out of the cell

the diffusion of free water across a selectively permeable membrane

swollen or distended, as in plant cells; a cell wall becomes this if it has a lower water potential than its surroundings, resulting in entry of watet

limp; lacking turgor (stiffness od firmness), as in a plant cell in surroundings where there is a tendency for water to leave the cell; a walled cell becomes this if it it as a higher water potential than its surroundings, resulting in a loss of water

a phenomenon in walled cells in which the cytoplasm shrivels and the plasma membrane pulls away from the cell wall; occurs when the cell loses water to a hypertonic environment

the passage of molecules or ions down their concentration gradient across a biological membrane with the assistance of specific transmembrane transport proteins, requiring no energy expenditure

the movement of a substance across a cell membrane against concentration gradient, mediated by specific transport proteins and requiring an expenditure of energy

the cellular secretion of biological molecules by the fusion of vesicles containing them with the plasma membrane

cellular uptake of biological molecules and particulate matter via formation of vesicles from the plasma membrane

a type of endocytosis in which large particulate substances or small organisms are taken up by the cell. It is carried out by some protists and by certain immune cells of animals (in mammals, mainly macrophages, neutrophils and dendritic cells)

a type of endocytosis in which the cell ingest extracellular fluids and its dissolved solutes

the movement of specific molecules into a cell by the inward budding of vesicles consisting proteins with receptor sites specific to the molecules being taken in; enables a cell to acquire bulk quantities of specific substances