Suppose that enzyme X catalyzes a reaction that involves the breakdown of a molecule. The product of this reaction is an amino acid. What molecule is the enzyme breaking down? A. a carbohydrate B. a lipid C. a protein D. a mineral

Which of the following is the source of energy for photosynthesis? a.) glucose b.) chlorophyll c.) carbon dioxide d.) sunlight

The kidney filters potentially toxic substances in the blood, and thus “clears” the blood of those substances. this clearance function is dependent upon and proportional to the diffusion gradient of the substance across filtering capillaries, i.e. if the concentration of the substance is doubled, twice as much will be cleared from each ml of blood that is filtered. suppose that the body produces a constant amount of a substance x per unit of time. the kidneys eliminate substance x at a rate directly proportional to the concentration of the substance and the volume of blood cleared each minute (c): elimination = c × [x], where [x] is the steady-state concentration of substance x. imagine an individual with an initial concentration of x equal to [x]0 who develops kidney disease. her baseline clearance c0 drops to one half of the original (½c0). what is the new steady state concentration of x? (for simplicity, assume that substance x is 100% filtered by the kidney).

Which best describes the scientific method? a. a path of clearly defined steps that must be followed in a particular order b. a possible answer to a scientific question based on knowledge or research c. the recipe for how to conduct an experiment that must be followed precisely d. the process of hypothesis and testing through which scientific inquiry occurs