Answer:
The correct answer is D. reactant.In any reaction (enzymatic or non-enzymatic), reactants are mentioned on the left hand side of the arrow while products are mentioned on the right hand side of the arrow.Enzyme name is usually mentioned above the arrow. Examples are shown in the figure.
Explanation:
<em><u>VERIFIED ANSWER</u></em>
<span>Positive feedback</span><span>
There are two types of feedback mechanisms
Positive feedback heightens the intensity
Negative feedback lowers the intensity
These all serve to maintain homeostasis. Homeostasis is the state where the internal and external part of the body maintains and establishes balance and equilibrium. </span>
First one is Model and second one is Inference
Answer:

point mutation, change within a gene in which one base pair in the DNA sequence is altered. Point mutations are frequently the result of mistakes made during DNA replication, although modification of DNA, such as through exposure to X-rays or to ultraviolet radiation, also can induce point mutations