5. What occurs when an enzyme and a substrate interact at an active site?
a. Activation energy is reduced.
b. The products are bound irreversibly.
c. The enzyme is changed by the reaction.
d. Activation energy is increased.

B

Explanation:

The enzime's active site bindes to the substrate when an enzime binds to a substrate it forms a enzime-substrate complex

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.