The vital link ensures continuity of species between organisms of one generation and the next is

Options

A. Zygote
B. Sperm
C. Pollen grain
D. Egg

Answer

To answer the question "The vital link ensures continuity of species between organisms of one generation and the next is," we need to analyze the options provided and understand the role of each in the reproductive process.

### Step-by-Step Solution:

1. **Understanding the Concept of Continuity of Species**:
- Continuity of species refers to the process by which organisms pass on their genetic material to the next generation. This is essential for the survival and evolution of species.

2. **Identifying the Options**:
- The options given are:
1. Zygote
2. Sperm
3. Pollen grain
4. Egg

3. **Analyzing Each Option**:
- **Zygote**: The zygote is formed by the fusion of male and female gametes (sperm and egg). It is a diploid cell that contains genetic material from both parents and represents the first stage of a new organism's development. This makes the zygote a crucial link between generations.
- **Sperm**: Sperm is the male gamete. While it plays a role in reproduction, it does not alone ensure continuity of species since it needs to fuse with an egg.
- **Pollen Grain**: Pollen grain is the male gamete in plants. Similar to sperm, it is essential for fertilization but does not directly link generations by itself.
- **Egg**: The egg is the female gamete. Like sperm, it is necessary for reproduction but does not ensure continuity of species on its own.

4. **Conclusion**:
- The zygote is the vital link that ensures continuity of species between generations because it is the result of the fusion of male and female gametes and develops into a new organism. Therefore, the correct answer is **Zygote**.

### Final Answer:
The vital link that ensures continuity of species between organisms of one generation and the next is **Zygote**.

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