Two celled stage of pollen grains is the result of

Options

A. Meiosis
B. symmetric mitosis
C. asymmetric mitosis
D. amitosis

Answer

To determine the answer to the question "Two celled stage of pollen grains is the result of?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Pollen Grain Development**:
- Pollen grains develop from pollen mother cells, which are diploid (2n).

2. **Meiosis Process**:
- The pollen mother cells undergo meiosis, a type of cell division that reduces the chromosome number by half. This process results in the formation of haploid microspores.

3. **Formation of Microspore Tetrad**:
- During meiosis, the microspores are produced in a tetrad arrangement (four microspores together).

4. **Mitosis of Microspores**:
- Each haploid microspore then undergoes mitosis. However, this mitosis is asymmetric, meaning that the spindle fibers do not divide the cell equally.

5. **Two-Celled Stage**:
- Due to this asymmetric mitosis, the microspores develop into a two-celled stage, consisting of:
- A larger vegetative cell
- A smaller generative cell

6. **Further Development**:
- The generative cell can undergo further mitosis to form two male gametes, leading to a three-celled stage, but the question specifically asks about the two-celled stage.

7. **Identifying the Correct Answer**:
- The options provided were:
- A) Meiosis
- B) Symmetric Mitosis
- C) Asymmetric Mitosis
- D) Amitosis
- The correct answer is **C) Asymmetric Mitosis**, as this is the process that leads to the formation of the two-celled stage of pollen grains.

### Final Answer:
The two-celled stage of pollen grains is the result of **asymmetric mitosis**.

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