DNA Replication Overview

This set of flashcards covers essential vocabulary and concepts related to DNA replication as presented in lecture notes.

What is the primary genetic material for all known organisms?

Double-stranded DNA (dsDNA) is the genetic material for all known organisms.

What is the difference between RNA and DNA in terms of structure?

RNA usually exists as a single strand, has ribose sugar instead of deoxyribose, and uses uracil instead of thymine.

What are dNTPs?

Deoxynucleoside triphosphates (dNTPs) are the building blocks for DNA synthesis, including dATP, dGTP, dCTP, and dTTP.

Which enzyme is responsible for catalyzing DNA synthesis?

DNA polymerase is the enzyme that catalyzes DNA synthesis from deoxyribonucleotides.

What role do Mg++ ions play in DNA replication?

Mg++ ions are required for the function of enzymes involved in DNA replication.

How does a new DNA polymer form?

A new DNA polymer is formed by adding monomer nucleotides to the 3'-OH end via a dehydration reaction.

What is the significance of primers in DNA synthesis?

Primers provide a free 3'-OH end required for DNA polymerase to initiate synthesis.

What are Okazaki fragments?

Okazaki fragments are short segments of newly synthesized DNA on the lagging strand during DNA replication.

What is the function of the sliding clamp during DNA replication?

The sliding clamp holds DNA polymerase on the template strand during synthesis.

What happens during mismatch repair?

Mismatch repair fixes mispaired bases and small insertions or deletions that occur during DNA synthesis.

What role does DNA ligase play in DNA replication?

DNA ligase seals gaps between sugar-phosphate backbones of adjacent DNA fragments.

What condition is caused by a defect in endonucleases that repair UV-induced damage?

Xeroderma pigmentosum (XP) is a condition caused by a defect in endonucleases that remove UV-induced pyrimidine dimers.

Why is DNA considered to determine characteristics of a cell indirectly?

DNA determines every characteristic of a cell or organism indirectly through the properties of specific proteins.

What process involves the removal of pyrimidine dimers caused by UV light?

Nucleotide excision repair removes pyrimidine dimers formed by UV radiation.

What is the rate of nucleotide mispairing during DNA synthesis by DNA polymerase III?

The rate of wrong nucleotide pairing during DNA synthesis is about 1 in 10^5.