In some organisms, karyokinesis is not followed by cytokinesis as a result of which, multinucleate condition arises leading to the formation of syncytium. The perfect example for this is

Options

A. Appearance of a furrow in cell membrane
B. Liquid endosperm in coconut
C. Sexual reproduction
D. Fertilisation

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Karyokinesis and Cytokinesis**:
- Karyokinesis refers to the division of the nucleus during cell division, while cytokinesis is the process that follows, where the cytoplasm divides to form two separate cells.

2. **Identifying the Condition of Syncytium**:
- A syncytium is a multinucleate condition that arises when karyokinesis occurs without subsequent cytokinesis. This means that multiple nuclei exist within a single cell due to the absence of cytoplasmic division.

3. **Examples of Syncytium Formation**:
- In certain organisms, this condition can be observed. The question asks for a perfect example of this phenomenon.

4. **Analyzing the Options**:
- The options provided include:
- The appearance of a furrow in the cell membrane
- The liquid endosperm in coconut
- Sexual reproduction
- Fertilization
- Among these, the appearance of a furrow indicates cytokinesis, which is not relevant to syncytium. Sexual reproduction and fertilization do not directly relate to the multinucleate condition.

5. **Identifying the Correct Example**:
- The liquid endosperm in coconut is a prime example of syncytium formation. In coconuts, the endosperm is produced through karyokinesis without cytokinesis, resulting in a liquid form that nourishes the developing embryo.

6. **Conclusion**:
- Therefore, the perfect example of an organism where karyokinesis is not followed by cytokinesis, leading to the formation of a syncytium, is the liquid endosperm in coconut.

**Final Answer**: The perfect example for this is the liquid endosperm in coconut.

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