How do temperature and ph affect an enzyme that a chemical reaction depends on ? a) they can break down the reactants b) they can break down the products c) they can change the shape of an enzyme d) they can cause the chemical reaction to reverse

the sphincter muscles at the end of the digestive tract is the anus.

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.