The answer to your question is A.
An exothermic chemical reaction is change in the chemicals that can never be undone, an exothermic solution is a combination of chemicals
Answer:
Mutations of enzymes involved in nucleotide excision repair.
Explanation:
- Xeroderma pigmentosum is a genetic disorder and the person suffering from this disorder is sensitive to ultraviolet light due to the disability of the enzymes involved in nucleotide excision repair which prevents DNA damage caused by ultraviolet light.
- Thus, the individuals are sensitive to the exposure of UV and suffer severe problems when exposed to sunlight.
- The major cause of the disorder is the inability to repair DNA damage caused by exposure to sunlight due to the mutation in an enzyme involved in nucleotide excision repair.
- Nucleotide excision repair is a DNA repair process that can excise out single-stranded DNA that is damaged by UV.
- UV exposure leads to the addition of bulky adducts in the DNA known as thymine dimers. The enzymes of NER are involved in the removal of these adducts by excising out a segment of DNA that contains such lesions.
- However, in the case of XP, the mutations make this repair system non-functional or partially functional and thus, the individual becomes highly sensitive to UV exposure.
Research has demonstrated that neural stem cells have an impaired ability to differentiate into functional neurons when subjected to ethanol. They found out that treating cultured neural system impairs their ability to differentiate in functioning neurons. With this impairment it seems to be united with aberrant, dense methylation and loci which are active in normal tissue.
The answer to this question is b syphillis because of cervical discharge
