Question

the enzyme dna polymerase i, discovered by arthur kornberg in 1956, plays a crucial role in dna replication and repair. this enzyme is responsible for removing rna primers from the okazaki fragments and replacing them with dna. dna polymerase i has three distinct activities: a 5 to 3 dna polymerase activity, a 3 to 5 exonuclease activity, and a 5 to 3 exonuclease activity. the 5 to 3 exonuclease activity is particularly important for the removal of rna primers. mutations in the gene encoding dna polymerase i can lead to severe defects in dna replication and repair, resulting in genomic instability and increased susceptibility to mutations. studies have shown that these mutations can cause a variety of genetic disorders, including some forms of cancer.
10
which choice best describes the main purpose of the text?
a to discuss the historical discovery of dna polymerase i by arthur kornberg
b to explain the process of dna replication and the role of rna primers
c to detail the various mechanisms involving dna polymerase i and their importance
d to highlight the significance of dna polymerase i in maintaining genomic stability

Explanation:

• Option A: The text mentions the discovery of DNA polymerase I by Arthur Kornberg but focuses more on the enzyme's activities and importance, not just the historical discovery. So A is incorrect.
• Option B: The text is about DNA polymerase I, not primarily about the process of DNA replication and the role of RNA primers (though RNA primers are mentioned in relation to the enzyme). So B is incorrect.
• Option C: The text details the three activities of DNA polymerase I, its role in removing RNA primers, and the consequences of mutations in the gene encoding it, all of which are mechanisms involving the enzyme and their importance. This option aligns well with the content.
• Option D: While the text mentions that mutations can lead to genomic instability, the main focus is not just on highlighting the enzyme's significance in maintaining genomic stability but on the various mechanisms and aspects of the enzyme. So D is not the best choice.

Answer:

C. To detail the various mechanisms involving DNA polymerase I and their importance