Enzymes can accelerate reactions by:. A) binding a substrate or substrates.
B) promoting the removal or addition of protons.
C) correctly positioning a metal ion for catalysis.
D) lowering the energy for activation.
E) all of the above.

D) lowering the energy for activation.

Explanation:

Just like chemical catalysts that accelerate the rate of chemical reactions, enzymes are biological catalysts that accelerate the rate of biochemical reactions.

Majorly, a catalyst works by lowering the activation energy required for a specific reaction. The lower the activation energy for a reaction, the faster the rate of that particular reaction.

Hence, an enzyme accelerates the rate of reaction by lowering activation energy of the reaction.

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

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