How many cells are present in a mature pollen grain .explain

Answer

To answer the question "How many cells are present in a mature pollen grain?" we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding Pollen Grain Formation**:
- Pollen grains are formed from the microsporangia, which contain a tissue known as sporogenous tissue. This tissue consists of microspore mother cells.

2. **Microsporogenesis**:
- Each microspore mother cell undergoes meiosis to produce four microspores. This process is known as microsporogenesis. The four microspores can be found in a structure called a pollen tetrad.

3. **Development of Pollen Grain**:
- Each pollen grain develops from one of the microspores. Initially, the pollen grain is a single cell.

4. **Mitosis in Pollen Grain**:
- The single pollen grain undergoes mitosis, resulting in two distinct cells: a larger vegetative cell and a smaller generative cell.

5. **Further Division of Generative Cell**:
- The generative cell then undergoes another mitotic division, resulting in the formation of two male gametes.

6. **Counting the Cells**:
- Therefore, a mature pollen grain consists of:
- 1 vegetative cell
- 2 male gametes
- In total, this gives us 3 cells in a mature pollen grain.

### Conclusion:
A mature pollen grain contains **3 cells**: one vegetative cell and two male gametes.

---