Male gametes in angiosperms are formed by :

Options

A. Mitotic division in vegetative cell
B. Meiotic division in pollen mother cell
C. Meiotic division in vegetative cell
D. Mitotic division in generative cell

Answer

To solve the question "Male gametes in angiosperms are formed by:", we need to understand the process of male gamete formation in flowering plants (angiosperms). Here’s the step-by-step solution:

### Step 1: Identify the Structure of Pollen Grains
- In angiosperms, male gametes are contained within pollen grains.
- Pollen grains are typically spherical and consist of two main cells: a vegetative cell and a generative cell.

**Hint:** Remember that pollen grains are the male gametophytes in angiosperms.

### Step 2: Understand the Role of the Vegetative Cell
- The vegetative cell is larger and contains abundant food reserves. It has an irregularly shaped nucleus.
- Its primary role is to support the generative cell and facilitate the growth of the pollen tube.

**Hint:** The vegetative cell provides nourishment and structure to the pollen grain.

### Step 3: Understand the Role of the Generative Cell
- The generative cell is smaller and floats within the cytoplasm of the vegetative cell.
- In most angiosperms (about 60%), the pollen grains are shed at the two-celled stage (one vegetative cell and one generative cell).

**Hint:** The generative cell is crucial for male gamete formation.

### Step 4: Division of the Generative Cell
- In species where the generative cell divides, it undergoes mitotic division.
- This division results in the formation of two male gametes.

**Hint:** Focus on the fact that the generative cell divides mitotically to produce male gametes.

### Step 5: Conclusion
- The correct answer to the question is that male gametes in angiosperms are formed by mitotic division in the generative cell.

**Final Answer:** Male gametes in angiosperms are formed by mitotic division in the generative cell.

### Summary of Steps:
1. Identify pollen grain structure (vegetative and generative cells).
2. Understand the role of the vegetative cell.
3. Understand the role of the generative cell.
4. Recognize the division of the generative cell (mitotic division).
5. Conclude with the correct answer.