5 Written questions
5 Matching questions
- endergonic reaction
- active site
- a The spontaneous tendency of a substance to move down its concentration gradient from where it is more concentrated to where it is less concentrated.
- b An energy-requiring chemical reaction, which yields products with more potential energy than the reactants. The amount of energy stored in the products equals the difference between the potential energy in the reactants and that in the products.
- c Cellular uptake of molecules or particles via formation of new vesicles from the plasma membrane.
- d The part of an enzyme molecule where a substrate molecule attaches (by means of weak chemical bonds); typically, a pocket or groove on the enzyme's surface.
- e A nonprotein molecule or ion that is required for the proper functioning of an enzyme. See also coenzyme.
5 Multiple choice questions
- The change in shape of the active site of an enzyme, induced by entry of the substrate so that it binds more snugly to the substrate.
- Energy available in molecules for release in a chemical reaction; a form of potential energy.
- Referring to a solution that, when surrounding a cell, will cause the cell to lose water.
- A substance that reduces the activity of an enzyme by binding to the enzyme's active site in place of the substrate. A competitive inhibitor's structure mimics that of the enzyme's substrate.
- The movement of materials out of the cytoplasm of a cell by the fusion of vesicles with the plasma membrane.
5 True/False questions
metabolism → The totality of an organism's chemical reactions.
second law of thermodynamics → The principle whereby every energy conversion reduces the order of the universe, increasing its entropy. Ordered forms of energy are at least partly converted to heat.
noncompetitive inhibitor → A substance that reduces the activity of an enzyme by binding to the enzyme's active site in place of the substrate. A competitive inhibitor's structure mimics that of the enzyme's substrate.
coenzyme → An organic molecule serving as a cofactor. Most vitamins function as coenzymes in important metabolic reactions.
feedback inhibition → A method of metabolic control in which a product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway.