Consider the following events in DNA replication
1. Formation of RNA primers by RNA polymerase.
2. Removal of RNA primers and formation of Okazaki fragments.
Formation of DNA strands on RNA primers by DNA polyIII complex.
4. Recognition of intiation point by initiator protein.
5. Dissociation of hydrogen bonds and opening of a 'bubbble' in the duplex by unwinding proteins.
6. Filling up of the gaps between Okazaki fragments and formation of DNA strand. The correct sequence of these events is:-

Options

A. 4,5,1,3,2,6
B. 4,1,5,,2,6,3
C. 5,4,2,1,3,6
D. 4,2,1,5,3,6

Answer

To determine the correct sequence of events in DNA replication, we can analyze the provided steps systematically. Here’s the step-by-step solution:

### Step-by-Step Solution:

1. **Recognition of Initiation Point by Initiator Protein (Step 4)**:
- The first step in DNA replication is the recognition of the initiation point by initiator proteins. These proteins bind to specific sequences in the DNA to begin the replication process.

2. **Dissociation of Hydrogen Bonds and Opening of a 'Bubble' in the Duplex by Unwinding Proteins (Step 5)**:
- After the initiation point is recognized, unwinding proteins (helicases) break the hydrogen bonds between the two strands of DNA, creating a replication bubble.

3. **Formation of RNA Primers by RNA Polymerase (Step 1)**:
- Once the DNA strands are separated, RNA polymerase synthesizes short RNA primers. These primers are essential for DNA polymerases to initiate DNA synthesis.

4. **Formation of DNA Strands on RNA Primers by DNA Polymerase III Complex (Step 3)**:
- DNA polymerase III then extends the RNA primers, synthesizing new DNA strands complementary to the template strands.

5. **Removal of RNA Primers and Formation of Okazaki Fragments (Step 2)**:
- In the case of lagging strand synthesis, RNA primers are removed and replaced with DNA. This process leads to the formation of Okazaki fragments.

6. **Filling Up of the Gaps Between Okazaki Fragments and Formation of DNA Strand (Step 6)**:
- Finally, the gaps between the Okazaki fragments are filled in by DNA polymerase, resulting in a continuous DNA strand.

### Correct Sequence:
The correct sequence of events is:
- 4 (Recognition of initiation point by initiator protein)
- 5 (Dissociation of hydrogen bonds and opening of a 'bubble' in the duplex by unwinding proteins)
- 1 (Formation of RNA primers by RNA polymerase)
- 3 (Formation of DNA strands on RNA primers by DNA polymerase III complex)
- 2 (Removal of RNA primers and formation of Okazaki fragments)
- 6 (Filling up of the gaps between Okazaki fragments and formation of DNA strand)

### Final Answer:
The correct sequence is: **4, 5, 1, 3, 2, 6**.