| A | B |
|---|
| energy | to move matter in a direction it would not move if let alone |
| kinetic energy | energy that is actually doing work |
| heat | the energy associated with the movement of molecules in a body of matter |
| potential energy | stored energy |
| chemical energy | the potential energy of molecules, the most important type of energy for living organisms |
| thermodynamics | the study of energy transformations that occur ina collection of matter |
| first law of thermodynamics | the law of energy conservation, the total amount of energy in the universe that is constant |
| second law of thermodynamics | states that energy conversions reduce the order of the universe |
| entropy | the amount of disorder in a system |
| endergonic reactions | (endergonic- energy in)these reactions yeild products that have lots of potential energy |
| exergonic rections | a chemical reaction that realeases energy |
| cellular respiration | the energy releasing chemical breakdown of glucose molecules and the storage of he energy in a form that the cell can use to do work |
| cellular metabolism | the chemical activites of cells |
| energy coupling | in cellular metabolism, the use of energy released from exergonic reactions todrive essential endergonic reactions |
| phosphorylation | the transfer of a phosphate group, usually from ATP, to a molecule |
| energy of activation | the amount of energy that reactants must absorb before a chemical reaction will start |
| enzyme | a protein that serves as a biological catalyst |
| substrate | a specific substance on which an enzyme acts |
| active site | the part of an enzyme molecule where a substrate molecule attaches |
| cofactors | a nonprotein substance that helps an enzyme catalyze a metabolic reaction |
| coenzyme | an organic substance that acts as a cofactor helping n enzyme catalyze a metabolic reaction |
| competitive inhibitor | resembles the enzyme's normal substrate and competes with the substrate for the active site on the enzyme |
| noncompetitive inhibitor | does not enter the active site |
| negative feedback | a type of inhibition where a metabolic reaction is blocked by its products |
| selective permeability | a property of biological membrane that allows some substances to cross more easily than others and blocks the passage of other substances altogther |
| fluid mosaic | a description of a membrane structure |
| receptors | chemical messangers from other cells |
| signal transduction | a chai reaction involving other proteins |
| diffusion | the tendency of molecular order to become disordered |
| pasive transport | the diffusion of a substance across a biological membrane |
| concentration gradient | a regular increase or decrease in the intensity or density of a chemical substance |
| osmosis | diffusion of water molecules across a seletivly permeable membrane |
| hypertonic | a solution with a higher concentration of solutes |
| hypotonic | a solution with a lower solute concentration |
| osmoregulation | the control of water balance |
| facilitated diffusion | when one protein makes it possible for a substance to move down its concentration gradient |
| active transport | when a cell expand energy to move molecules across a membrane |
| exocytosis | a process a cell uses to export bulky materials from its cytoplasm |
| endocytosis | a cell takes in macromolecules or other particles by forming vesicles or vacuoles froms its plasma membrane |
| phagocytosis | cellular eating |
| pinocytosis | cellular drinking |
| receptor-mediated endocytosis | a third type of endocytosis |
| hypercholesterolemia | an excessivly high level of cholesterol in the blood |
