A greater amount of DNA damage occurs when a living organism is exposed to a greater amount of a radioactive isotope. How might
this affect the number of mutations acquired by the organism? A. More mutations will be acquired, leading to more phenotypic changes.
B. The number of mutations will be the same because the same isotope was used. C. There will be no mutations because damaged DNA is always repaired perfectly. D. Fewer mutations will be acquired, leading to fewer phenotypic changes.
Option A, More mutations will be acquired, leading to more phenotypic changes
Explanation:
Radioactive material causes mutations in living organisms. Radioactivity is very harmful to living cells as it is ionizing in most of the cases which means it can remove an electron from an atom. When DNA in a human cell is exposed to radiation, its structure may get disrupted thereby causing loss of electrons and hence mutation. The mutated cell will not function like a normal cell and also the repair process of cell is slow. Therefore, once a cell is mutated it takes years to repair and there are high chances that it does not get repaired ever and is just carried to next generation.
These mutated cell will express certain distorted physical trait (phenotype). Thus, option A, is correct
