Use the dichotomous key shown below to identify the plant shown in the picture above. 1.a. leaves have sharp, thornlike spines along their edges american holly. 1.b. leaves do not have sharp, thornlike spines along their edges go to 2. 2.a. has three or more leaflets growing from a single point go to 3. 2.b. does not have three or more leaflets growing from a single point greenbrier. 3.a. has a total of three leaflets growing from a single point eastern poison ivy. 3.b. has a total of five leaflets growing from a single point virginia creeper. a. american holly b. eastern poison ivy c. greenbrier d. virginia creeper

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).