The prokaryotes are unicellular organisms that lack organelles or other internal membrane-bound structures. Therefore, they do not have a nucleus, but, instead, generally have a single chromosome: a piece of circular, double-stranded DNA located in an area of the cell called a nucleoid
Genetic variation results in different forms, or alleles?, of genes. For example, if we look at eye colour, people with blue eyes have one allele of the gene for eye colour, whereas people with brown eyes will have a different allele of the gene
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- C Genetic Drift Geographic Isolation.
