In Cycas , fertilisation occurs through

Options

A. Isogamy
B. Siphonogamy
C. Zoidiogamy
D. Both B and C.

Answer

**Step-by-Step Solution:**

1. **Understanding Cycas**: Cycas is a genus of plants belonging to the family Cycadaceae. It is an ancient group of trees that reproduce through specific fertilization methods.

2. **Identifying Fertilization Types**: The question asks about the type of fertilization that occurs in Cycas. The options provided are:
- A) Isogamy
- B) Siponogamy
- C) Zoidogamy
- D) Both B and C

3. **Analyzing Each Option**:
- **Isogamy**: This refers to a type of fertilization where gametes are similar in size and shape. This is not applicable to Cycas.
- **Siponogamy**: This is a process where pollen tubes are formed to transfer male gametes to the female gametes. This method is observed in Cycas.
- **Zoidogamy**: This type involves the swimming of male gametes through water to reach the female gametes. This method is also observed in Cycas.

4. **Conclusion**: Since Cycas exhibits both siponogamy and zoidogamy, the correct answer to the question is option D) Both B and C.

5. **Final Answer**: In Cycas, fertilization occurs through both siponogamy and zoidogamy.

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