Answer:
5 bases
Explanation:
If there are 17 amino acids and only 2 bases that can be combined in order to make a codon then:
for 4 bases 
is 16 and it is not enough combination for all 17 amino acids
for 5 bases 
is 25 combinations (meaning that more than one codon could code for the same amino acid).
Polygenic is a<span> </span>trait<span> that is controlled by a group of </span>nonallelic <span>genes. </span>For example, humans can be many different sizes. Height is a polygenic trait, controlled by at least three genes with six alleles. If you are dominant for all of the alleles for height, then you will be very tall. ... Skin color is also a polygenic trait, as are hair and eye color. A trait that is controlled by a group of nonallelic <span>genes
</span>
Answer:
The correct answer will be option-E.
Explanation:
The nervous system is one of the most important systems of the animal body which helps in the transmission of the signals to and fro from the body to the nervous system.
The evolution of this system is the basis of the evolution of the human species as it helped and tried the species to sense the external environment most efficiently as well as improved the response to the environment.
The nervous system improved the response by forming new interactions with each other and responding to it by reducing the response time through reflex actions which formed fast acting response to the environment. The transmission of signals improved as the cells were long-lasting that is present form the birth of an organism
Thus, option-E is the correct answer.
