Those that do not show artificial selection are examples A and B.
Answer: Point mutation is easily reversible, thus non-lethal
Explanation:
Point mutation is caused by exchange of a single nucleotide for another. These change is called
1) Transition (when a purine base substitute another purine base, or pyrimidine bases substitute each other)
2) Transversion (when a purine base substitute a pyrimidine base).
However, note that a point mutation can be easily reversed by another point mutation; so, the claim that a nucleotide difference in the Hsr12 gene caused the human disease is inaccurate
Answer:
D. Enzymes open the DNA strand, remove a segment of DNA from the strand that contains the damage, and resynthesize the correct DNA sequence.
Explanation:
From time to time, the DNA gets exposed to certain chemicals or radiation that damages it. However, the cell has a DNA repair mechanism in place called NUCLEOTIDE EXCISION REPAIR (NER).
NUCLEOTIDE EXCISION REPAIR (NER) is one of the DNA repair mechanisms in which certain enzymes open the DNA strand, remove a segment of DNA that contains the damaged gene or nucleotide bases, and resynthesize the correct DNA sequence using the pair of the damaged one.
