When pollen tube enters by integuments then the process is called

Options

A. (a) porogamy
B. (b) mesogamy
C. (c) chalazomany
D. (d) syngamy

Answer

**Step-by-Step Solution:**

1. **Understanding Pollen Tube Entry**: The question asks about the process when the pollen tube enters the embryo sac through the integuments. This is a specific type of fertilization mechanism in flowering plants.

2. **Identifying the Types of Pollen Tube Entry**: There are several ways through which the pollen tube can enter the embryo sac:
- **Porogamy**: The pollen tube enters through the micropyle.
- **Mesogamy**: The pollen tube enters through the integuments.
- **Chelazogamy**: The pollen tube enters through the chalazal end.
- **Syngamy**: This is not a method of entry but refers to the fusion of male and female gametes.

3. **Focusing on Mesogamy**: Since the question specifically mentions the pollen tube entering through the integuments, we identify that this process is called **mesogamy**.

4. **Conclusion**: Therefore, the answer to the question is **mesogamy**.

**Final Answer**: When the pollen tube enters by integuments, the process is called **mesogamy**.

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