D1.1 DNA replication (Molecules): แบบฝึกหัด

In humans, telomeres are repetitive DNA sequences at the ends of chromosomes. Which of the following statements best explains the role of telomeres and the enzyme telomerase in cellular processes?

During DNA replication, DNA polymerase III is responsible for adding nucleotides to the growing strand. However, errors can occur. Which of the following mechanisms primarily contributes to the high fidelity of DNA replication in preventing and correcting these errors?

The lagging strand during DNA replication is synthesized discontinuously. Which combination of enzymes is directly involved in the synthesis and eventual joining of these discontinuous segments, known as Okazaki fragments?

Explain why DNA replication is considered semi-conservative.

Differentiate between the functions of DNA polymerase III and DNA polymerase I during prokaryotic DNA replication.

Explain why the enzyme DNA primase is essential for the initiation of DNA synthesis by DNA polymerase III.

Describe the semi-conservative process of DNA replication, outlining the specific roles of the following enzymes and proteins: DNA helicase, DNA gyrase (topoisomerase), single-strand binding proteins, DNA primase, DNA polymerase III, DNA polymerase I, and DNA ligase. Explain how the leading and lagging strands are synthesized differently and why this difference is necessary.

The process of DNA replication involves a series of highly coordinated steps to ensure the entire genome is copied accurately before cell division. This complexity arises from both the chemical structure of the DNA molecule and the specific requirements of the enzymes involved.