Answer:
The replacement of a base at a codon, as occurs when the GGA codon is changed to CGA, causes a change in the amino acid glycine to arginine.
Explanation:
Nitrogen base changes in a codon usually result from base changes in the DNA before transcription into messenger RNA, called point gene mutations.
In the case presented, the substitution of the guanine base by cytosine in the GGA codon —resulting in a CGA codon— generates a change in the coding amino acid, resulting in arginine instead of glycine.
The change of an amino acid in a peptide or protein can mean an alteration in the structure or function of these molecules.
Because an amino acid can be encoded by several codons, changes of a nitrogen base at a codon sometimes do not involve changes in the amino acid sequence of a protein.
Answer:
Major histocompatibility complex (MHC) antigens
Explanation:
The process in which recipient body rejects the transplanted organ is called a allograft rejection or transplantation rejection.
A transplanted organ contains Major histocompatibility complex (MHC) antigens which are required to be accepted by the recipient's body to function properly but T cells in recipient's body become alloreactive and recognize MHC antigens (donor-derived antigens) as foreign and starts making antibodies against it. Which means the recipient's body is rejecting the transplanted organ.
Hence, the correct answer is "Major histocompatibility complex (MHC) antigens".
Answer:
B
Explanation:
This involves selectively breeding two or more populations of a species or subspecies with desirable traits that are wanted by the humans. The offspring of the populations will bear the desired traits from the population. Breeding can be done over generations. An example is the breeding a cattle population that is resistant to drought and another that produces more milk. The filial generations will bear both traits.
The protons have to stay the same
