Which of the following events does not take place after the degeneration of the generative cell in pollen grain ?

Options

A. Entry of pollen tube inside the embryosac
B. Fertilization
C. Only triple fusion but not syngamy
D. Neither entry of pollen - tube inside the embryosac nor fertilization

Answer

To solve the question "Which of the following events does not take place after the degeneration of the generative cell in pollen grain?", we can follow these steps:

### Step 1: Understand the Role of the Generative Cell
- The generative cell in a pollen grain is responsible for producing male gametes (sperm cells). When the generative cell degenerates, it means that these male gametes are no longer produced.

**Hint:** Recall the function of the generative cell in pollen grains and its role in fertilization.

### Step 2: Analyze the Options
- We have the following options:
1. Entry of pollen tube inside embryo sac
2. Fertilization of male gamete
3. Triple fusion but not syngamy

**Hint:** Consider what happens to the pollen tube and fertilization processes when the generative cell is absent.

### Step 3: Evaluate Each Option
- **Option 1: Entry of pollen tube inside embryo sac**
- The pollen tube can still enter the embryo sac even if the generative cell degenerates. The pollen tube's primary role is to deliver the sperm cells to the ovule.

- **Option 2: Fertilization of male gamete**
- Fertilization requires the presence of male gametes. If the generative cell has degenerated, then no male gametes are available for fertilization. Therefore, this event cannot take place.

- **Option 3: Triple fusion but not syngamy**
- Triple fusion involves the fusion of one male gamete with two polar nuclei, which can occur if at least one male gamete is available. However, if the generative cell is gone, fertilization (syngamy) cannot occur.

**Hint:** Think about the definitions of syngamy and triple fusion and how they relate to the presence of male gametes.

### Step 4: Conclusion
- Based on the analysis, the event that does not take place after the degeneration of the generative cell is **Option 2: Fertilization of male gamete**. Without the generative cell, there are no male gametes available for fertilization.

**Final Answer:** Fertilization of male gamete does not take place after the degeneration of the generative cell in pollen grain.