Which of the following is the substrate for DNA ligase?

Which of the following is the substrate for DNA ligase?

• A. Okazaki fragments
• B. DNA polymerase
• C. RNA primers
• D. Nucleotides

Answer: (A)

DNA ligase is an enzyme crucial for the final stages of DNA replication and repair, and its primary function is to join together DNA fragments. The correct substrate for DNA ligase is Okazaki fragments, which are the short sequences of DNA that are synthesized on the lagging strand during DNA replication. During replication, there are continuous and discontinuous syntheses of DNA. On the leading strand, DNA is synthesized continuously, while on the lagging strand, it is synthesized in small sections called Okazaki fragments. Once the DNA polymerase finishes synthesizing these fragments, DNA ligase comes in to join the ends of these fragments together, creating a continuous DNA strand. This function is vital for ensuring the integrity of the DNA molecule, allowing the complete and accurate transmission of genetic information. The other options, such as DNA polymerase and RNA primers, refer to different components of the replication process or are not substrates that DNA ligase acts upon directly. Similarly, nucleotides are the building blocks of DNA but are not the specific substrate for ligation by DNA ligase.

DNA ligase is an enzyme crucial for the final stages of DNA replication and repair, and its primary function is to join together DNA fragments. The correct substrate for DNA ligase is Okazaki fragments, which are the short sequences of DNA that are synthesized on the lagging strand during DNA replication.

During replication, there are continuous and discontinuous syntheses of DNA. On the leading strand, DNA is synthesized continuously, while on the lagging strand, it is synthesized in small sections called Okazaki fragments. Once the DNA polymerase finishes synthesizing these fragments, DNA ligase comes in to join the ends of these fragments together, creating a continuous DNA strand.

This function is vital for ensuring the integrity of the DNA molecule, allowing the complete and accurate transmission of genetic information. The other options, such as DNA polymerase and RNA primers, refer to different components of the replication process or are not substrates that DNA ligase acts upon directly. Similarly, nucleotides are the building blocks of DNA but are not the specific substrate for ligation by DNA ligase.