Which of the following feature is universal in all sexually reproducing organisms ?

Options

A. Embryo formation
B. Gametic meiosis
C. Zygote formation
D. Pollen grain transfer

Answer

To determine which feature is universal in all sexually reproducing organisms, we can analyze the options provided: embryo formation, gametic meiosis, zygote formation, and pollen grain transfer.

### Step-by-Step Solution:

1. **Understanding Sexual Reproduction**:
- Sexual reproduction involves the fusion of male and female gametes. The male gamete is called sperm, and the female gamete is called the egg.

2. **Identifying the Key Features**:
- **Embryo Formation**: This occurs after the zygote has formed and undergone several divisions. However, not all sexually reproducing organisms develop into embryos in the same way (e.g., some organisms may not have a distinct embryonic stage).
- **Gametic Meiosis**: This is the process by which gametes are produced through meiosis. While meiosis is common in many sexually reproducing organisms, it is not a universal feature since some organisms may reproduce asexually or have different reproductive strategies.
- **Zygote Formation**: This is the result of the fertilization of the egg by the sperm, leading to the formation of a zygote. This process is fundamental to all sexually reproducing organisms.
- **Pollen Grain Transfer**: This is specific to plants and involves the transfer of pollen from the male part of the flower to the female part. It is not applicable to all sexually reproducing organisms.

3. **Conclusion**:
- Among the options, zygote formation is the only feature that is universal in all sexually reproducing organisms. It is the first step in the development of a new organism following fertilization.

### Final Answer:
**Zygote formation is the universal feature in all sexually reproducing organisms.**

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