Evolution can be described as the changes which occur in a population over a period of time. Over a period of time, organisms tend to evolve those characteristics which make them better adapted to live in an environment. Such changes which occur over a long period of time are termed as evolution. Charles Darwin was the scientist to bring forward the theory of evolution.
The change in the tail length of a rat over a course of many years is an example of evolution.
<span>The operon binds to the RNA polymerase and releases the repressor.</span><span>
Amino acids like tryptophan and tyrosine are used to produce neurotransmitters and other products. Hormones such a serotonin and melatonin are made products of tryptophan as well as norepinephrine and adrenalin.</span>