nmdcat.online
BIO NMDCAT Structure of DNA
nmdcat.online July 3, 2026

92. A patient presents with skin lesions and a high vulnerability to UV-induced skin cancers, leading to a diagnosis of Xeroderma Pigmentosum. At the molecular level, this condition is caused by an inherited mutation in a gene that codes for an enzyme in the

A. Mismatch repair (MMR) pathway
B. Nucleotide excision repair (NER) pathway
✓
C. Homologous recombination (HR) pathway
D. Base excision repair (BER) pathway

📝 Explanation

XP is caused by defects in the NER pathway, which is responsible for cutting out UV-induced pyrimidine dimers and bulky DNA distortions.

📖 Additional Information

  • Mismatch repair (MMR) pathway
  • Nucleotide excision repair (NER) pathway
  • Homologous recombination (HR) pathway
  • Base excision repair (BER) pathway

XP is caused by defects in the NER pathway, which is responsible for cutting out UV-induced pyrimidine dimers and bulky DNA distortions.

🔗 Share This Question

Facebook Twitter LinkedIn WhatsApp

🧭 Navigate Questions

Previous Question

91. The treatment of a eukaryotic cell line with a specific drug blocks the activity of the enzyme histone deacetylase (HDAC). Biochemically, this inhibition maintains high levels of histone acetylation across the genome, forcing structural genes to remain inside

Next Question

93. A segment of double-stranded DNA is analyzed and found to have a melting temperature (Tm​) of 85∘C, while a second fragment of identical length melts at 72∘C. The physical explanation for the higher Tm​ of the first fragment is

Back to All Questions

🔗 Related MCQs

An increase in the incidence of ectopic pregnancies within a population can often be epidemiologically correlated with a prior increase in the prevalence of which sexually transmitted disease?
July 16, 2026
In the life cycle of Herpes Simplex Virus 2 (HSV-2), the virus travels along nerve fibers to reach the sensory ganglia. The cellular mechanism responsible for this retrograde transport utilizes:
July 16, 2026
A defining characteristic of the lesions associated with the secondary stage of syphilis is that they:
July 16, 2026
The causative agent of genital herpes, HSV-2, is enveloped. The biological significance of this viral envelope in the context of transmission is that it makes the virus:
July 16, 2026
The structural basis for the severe cardiovascular complications seen in tertiary syphilis, such as aortic aneurysms, is the chronic inflammation and destruction of:
July 16, 2026

Categories

View all →