The genome of the organisms constantly undergoes the state of damage. The damage may be caused by the mutagens, radiations and chemicals like intercalating agents. One of the mechanisms by which the DNA gets repaired is nucleotide excision repair. It is specified for repairing that DNA which has got damaged by the ultraviolet radiations. When the DNA is exposed to UV rays, the dimers of thymine and 6,4-photoproducts are formed which are quite bulky in size.
This damage is recovered by removing the short segment of single-stranded DNA that constitutes the lesion. The DNA polymerase uses the other single-stranded DNA as a template to form the short complementary strand. The DNA ligase then comes and serves its role of joining the strands together. In this way, the double-stranded DNA structure is retrieved.
Meiotic nondisjunction is much more likely than mitotic nondisjunction. Based on
A woman who is heterozygous, Bb, has brown eyes;
Explain why familial breast cancer shows a dominant pattern of inheritance in
How is an F′ factor different from an F factor?
With regard to the timing of conjugation, explain why the recipient
The raw material for evolution is random mutation. Discuss whether or
Why is an antibody used in this experiment? From
Explain the type of speciation (allopatric, parapatric, or sympatric
In fruit flies, curved wings are recessive to straight wings,
A recessive allele in mice results in an unusally long neck.
