Okazaki segments are small pieces of DNA and are formed on

Options

A. lagging strand
B. leading strand
C. sense strand
D. nonsense condons

Answer

To solve the question regarding where Okazaki segments are formed, we can break down the explanation into clear steps:

### Step-by-Step Solution:

1. **Understanding Okazaki Fragments**:
- Okazaki fragments are small pieces of DNA that are synthesized during DNA replication.

2. **DNA Structure**:
- DNA has a double helical structure, which consists of two strands running in opposite directions (antiparallel). Each strand has a directionality indicated as 5' to 3' and 3' to 5'.

3. **DNA Replication Process**:
- During DNA replication, the double helix unwinds to form a replication fork. This is where the DNA strands are separated to allow for copying.

4. **Role of DNA Polymerase**:
- DNA polymerase is the enzyme responsible for synthesizing new DNA strands. It can only add nucleotides in the 5' to 3' direction.

5. **Template Strand Orientation**:
- The template strand that is being copied must have a 3' to 5' orientation for the DNA polymerase to work effectively.

6. **Leading and Lagging Strands**:
- The strand that is continuously synthesized in the direction of the replication fork is called the leading strand.
- The other strand, which is synthesized in short segments away from the replication fork, is known as the lagging strand.

7. **Formation of Okazaki Fragments**:
- On the lagging strand, because of its orientation, DNA polymerase synthesizes short segments of DNA called Okazaki fragments. These fragments are formed because the polymerase must wait for the replication fork to open up more of the DNA.

8. **Conclusion**:
- Therefore, Okazaki fragments are formed on the lagging strand during DNA replication.

### Final Answer:
Okazaki segments are small pieces of DNA and are formed on the **lagging strand**.

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