Answer:
c. A to K
Explanation:
If the alanine mutation is restored to K or lysine residue, most likely the wild type level of activity can be restored. This is because, arginine and lysine have -NH2 as the functional group. So, functional similarity of arginine can be expected from lysine as well.
Hence the correct option is c that is A to K.
The phosphorus cycle does not include an atmospheric component because phosphorus does not cycle through the atmosphere. In comparison, important processes of the carbon and nitrogen cycle occur in the atmosphere.
Answer:
The correct answer would be 10.
The cell cycle can be divided into four phases namely gap 1 (G₁) phase , synthesis (S) phase, gap 2 (G₂) phase, and mitosis (M) phase.
DNA (deoxyribonuceic acid) content is only replicated and doubled in the S phase. However, the chromosome number remains the same. It can be explained as the number of chromosomes remains the same (2n) but number of chromatids doubles (4n) after S phase.
The number of chromatids restores to 2n in daughter cells after completion of mitosis.
Hence, if number of chromatids in metaphase was 20 i.e. 4n then the number of chromosomes (2n) would be 10.
Hence, 10 chromosomes or 5 pairs of chromosome would be present in the cell during its G₁ phase.