Answer:
The correct answer is "each of the MHC genes has a large number of alleles, but each individual only inherits two for each gene".
Explanation:
In normal conditions, an individual has only two different alleles for a given gene: one inherited from his mother and the other from his father. However, this does not mean that among humans, there are only two different alleles for each gene. The major histocompatibility (MHC) genes are a clear example of this, since there are multiple combinations for each MHC class. For instance, there are 40 very similar alleles only for the HLA-B27 subtype.
Answer: a. Primary level.
Explanation:
The primary level is characterized by the sequence of aminoacids of the protein, aminoacids have a carboxyl and an amino group bonded to a carbon atom, and are held together by peptide bonds between the carboxyl end of an aminoacid and the amino end of the next one, making an aminoacid chain.
Secondary, tertiary and quaternary levels determine the shape and thus the function of the protein according to different forces, hydrogen bonds take part in it bending the chain in different ways.
The answer is myelination. This involves the growth of myelin sheath around the axon or neurons, a biological process that occurs at a great pace in a child’s brain during child development after birth. The myelin sheath improves transmission of electrical impulses through a process called saltatory conduction (through hops).