5 Written questions
5 Matching questions
- facilitated diffusion
- active site
- active transport
- hypotonic solution
- a Referring to a solution that, when surrounding a cell, will cause the cell to take up water.
- b 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.
- c A nonprotein molecule or ion that is required for the proper functioning of an enzyme. See also coenzyme.
- d The passage of a substance through a specific transport protein across a biological membrane down its concentration gradient.
- e The movement of a substance across a biological membrane against its concentration gradient, aided by specific transport proteins and requiring input of energy (often as ATP).
5 Multiple choice questions
- Method by which organisms regulate solute concentrations and balance the gain and loss of water.
- Cellular "drinking"; a type of endocytosis in which the cell takes fluid and dissolved solutes into small membranous vesicles.
- In cellular metabolism, the use of energy released from an exergonic reaction to drive an endergonic reaction.
- The energy that matter possesses because of its location or arrangement. Water behind a dam and chemical bonds possess potential energy.
- The capacity to perform work, or to rearrange matter.
5 True/False questions
competitive 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.
heat → 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.
diffusion → The spontaneous tendency of a substance to move down its concentration gradient from where it is more concentrated to where it is less concentrated.
substrate → (1) A specific substance (reactant) on which an enzyme acts. Each enzyme recognizes only the specific substrate or substrates of the reaction it catalyzes. (2) A surface in or on which an organism lives.
fluid mosaic → A description of membrane structure, depicting a cellular membrane as a mosaic of diverse protein molecules embedded in a fluid bilayer made of phospholipid molecules.