DNA replication in eukaryotes occurs in the following steps:

1. **Initiation**: The process begins at specific points in the DNA known as origins of replication. At these points, proteins bind to the DNA and unwind it, creating a replication bubble. This unwinding is done by an enzyme called helicase.

2. **Unwinding**: The DNA double helix is unwound by the helicase, breaking the hydrogen bonds between the base pairs. This creates two single strands of DNA that will serve as templates for replication. Single-strand DNA-binding proteins bind to the separated strands to prevent them from re-forming a double helix.

3. **Primer Binding**: An enzyme called primase synthesizes a short RNA segment, known as a primer, which is complementary to the DNA sequence. The primer serves as a starting point for DNA synthesis.

4. **Elongation**: DNA polymerase enzymes add nucleotides to the 3' end of the primer, building a new strand of DNA. Because DNA synthesis can only occur in the 5' to 3' direction, one strand (the leading strand) is synthesized continuously, while the other (the lagging strand) is synthesized in short fragments known as Okazaki fragments.

5. **Primer Removal and Ligation**: The RNA primers are removed by an enzyme called RNase H, and the gaps where the primers were are filled in with DNA by DNA polymerase. The Okazaki fragments on the lagging strand are joined together by an enzyme called DNA ligase.

6. **Termination**: The process of replication ends when the replication forks meet and the newly synthesized DNA molecules are fully formed.

7. **Proofreading and Repair**: DNA polymerase also has proofreading ability. It can remove mispaired nucleotides and replace them with the correct ones. This ensures the accuracy of DNA replication.

This process ensures that each new cell has an exact copy of the DNA present in the original cell.

Question

DNA replication in eukaryotes occurs in the following steps:

1. **Initiation**: The process begins at specific points in the DNA known as origins of replication. At these points, proteins bind to the DNA and unwind it, creating a replication bubble. This unwinding is done by an enzyme called helicase.

2. **Unwinding**: The DNA double helix is unwound by the helicase, breaking the hydrogen bonds between the base pairs. This creates two single strands of DNA that will serve as templates for replication. Single-strand DNA-binding proteins bind to the separated strands to prevent them from re-forming a double helix.

3. **Primer Binding**: An enzyme called primase synthesizes a short RNA segment, known as a primer, which is complementary to the DNA sequence. The primer serves as a starting point for DNA synthesis.

4. **Elongation**: DNA polymerase enzymes add nucleotides to the 3' end of the primer, building a new strand of DNA. Because DNA synthesis can only occur in the 5' to 3' direction, one strand (the leading strand) is synthesized continuously, while the other (the lagging strand) is synthesized in short fragments known as Okazaki fragments.

5. **Primer Removal and Ligation**: The RNA primers are removed by an enzyme called RNase H, and the gaps where the primers were are filled in with DNA by DNA polymerase. The Okazaki fragments on the lagging strand are joined together by an enzyme called DNA ligase.

6. **Termination**: The process of replication ends when the replication forks meet and the newly synthesized DNA molecules are fully formed.

7. **Proofreading and Repair**: DNA polymerase also has proofreading ability. It can remove mispaired nucleotides and replace them with the correct ones. This ensures the accuracy of DNA replication.

This process ensures that each new cell has an exact copy of the DNA present in the original cell.

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