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.

phylogenetic tree is the tree of life or evolution tree. it shows the different branches of evolution. the sequence goes like tissues - coelom - backbone - endoskeleton - segmentation

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.