KROK 1 2013 – Question 153 · KROK (Medicine) · Biological Chemistry
An experiment proved that UV-irradiated skin cells of patients with xeroderma pigmentosum restore the native structure of DNA slower than the cells of healthy people due to the defect in repair enzyme. What enzyme takes part in this process?
- A. Endonuclease
- B. DNA gyrase
- C. RNA ligase
- D. DNA polymerase
- E. Primase
Hint
Consider the order of steps in excision repair of UV-induced damage and ask which enzymatic activity must act first, before gap-filling and sealing.
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