A rate-limiting enzyme catalyzes the first step in the conversion of a toxic metabolite to a urinary excretion product. Which of the following mechanisms for regulating this enzyme would provide the most protection to the body?

A. The product of the pathway should be an allosteric inhibitor of the rate-limiting enzyme.
B. The product of the pathway should act through gene transcription to decrease synthesis of the enzyme.
C. The toxin should act through gene transcription to increase synthesis of the enzyme.
D. The enzyme should have a high Km for the toxin.
E. The toxin allosterically activates the last enzyme in the pathway.

measuring light intensity

light meters can be used to measure light intensity. the meter is held at the soil surface and pointed in the direction of the maximum light intensity, and then the meter is read.

errors can be made when measuring light intensity by accidentally shading the light meter. the reliability of the results can be checked by taking many samples.

answer; hydrologic cycle;

i think i can answer even without the example. over time with environmental changes, sometimes a group of animals will adapt to better survive. take a moth for example. if the trees the moths use to camouflage themselves from predators, started to die or change colors themselves, the moths may, overtime of course, change color too. its just adapting to its surroundings. hope i was of any : )