5 Written questions
5 Matching questions
- hypertonic solution
- a The totality of an organism's chemical reactions.
- b Method by which organisms regulate solute concentrations and balance the gain and loss of water.
- c The study of energy transformation that occurs in a collection of matter. See first law of thermodynamics; second law of thermodynamics.
- d Thermal energy; the amount of energy associated with the movement of the atoms and molecules in a body of matter. Heat is energy in its most random form.
- e Referring to a solution that, when surrounding a cell, will cause the cell to lose water.
5 Multiple choice questions
- 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.
- The aerobic harvesting of energy from food molecules; the energy-releasing chemical breakdown of food molecules, such as glucose, and the storage of potential energy in a form that cells can use to perform work; involves glycolysis, the citric acid cycle, and oxidative phosphorylation (the electron transport chain and chemiosmosis).
- 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.
- A nonprotein molecule or ion that is required for the proper functioning of an enzyme. See also coenzyme.
- 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.
5 True/False questions
second law of thermodynamics → The principle of conservation of energy. Energy can be transferred and transformed, but it cannot be created or destroyed.
receptor-mediated endocytosis → The movement of specific molecules into a cell by the inward budding of membranous vesicles. The vesicles contain proteins with receptor sites specific to the molecules being taken in.
phosphorylation → The transfer of a phosphate group, usually from ATP, to a molecule. Nearly all cellular work depends on ATP energizing other molecules by phosphorylation.
concentration gradient → An increase or decrease in the density of a chemical substance in an area. Cells often maintain concentration gradients of ions across their membranes. When a gradient exists, substances tend to move from where they are more concentrated to where they are less concentrated.
hypotonic solution → Referring to a solution that, when surrounding a cell, will cause the cell to lose water.