How many nuclei is/are present in a fully developed male gametophyte?

Options

A. One
B. Two
C. Three
D. Four

Answer

To determine how many nuclei are present in a fully developed male gametophyte, we can follow these steps:

1. **Understanding Male Gametophyte Structure**: A male gametophyte, commonly known as pollen grain in flowering plants, is haploid (N) and consists of several nuclei.

2. **Identifying the Nuclei**: In a fully developed male gametophyte, there are typically two types of nuclei:
- **Sperm Nuclei**: There are two sperm nuclei present. These are the male gametes that will participate in fertilization.
- **Tube Nucleus**: There is one tube nucleus that is responsible for the growth of the pollen tube, which facilitates the delivery of the sperm nuclei to the ovule.

3. **Calculating the Total Number of Nuclei**:
- Total = Number of Sperm Nuclei + Number of Tube Nucleus
- Total = 2 (sperm nuclei) + 1 (tube nucleus) = 3 nuclei in total.

4. **Conclusion**: Therefore, a fully developed male gametophyte contains a total of 3 nuclei.

### Final Answer:
The number of nuclei present in a fully developed male gametophyte is **3**.

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