The basic forms of asexual reproduction are fission, budding gemmulation and fragmentation. Binary fission is common among

Options

A. bacteria and Protozoa
B. vertebrates and Protozoa
C. Primates and invertebrates
D. all chordates including humans

Answer

**Step-by-Step Solution:**

1. **Understanding Asexual Reproduction**: Asexual reproduction is a mode of reproduction that does not involve the fusion of gametes. It involves only one parent and results in offspring that are genetically identical to the parent.

2. **Types of Asexual Reproduction**: The question mentions four basic forms of asexual reproduction: fission, budding, gemmulation, and fragmentation. Each of these methods has distinct characteristics:
- **Fission**: This involves the splitting of a single organism into two or more parts, each capable of growing into a new organism.
- **Budding**: A new organism develops from a generative point on the parent organism.
- **Gemmulation**: This is the formation of a mass of cells that can develop into a new organism.
- **Fragmentation**: The parent organism breaks into fragments, and each fragment can grow into a new organism.

3. **Focusing on Binary Fission**: The question specifically asks about binary fission, which is a type of fission where the organism divides into two equal parts. This method is particularly common among certain organisms.

4. **Identifying Organisms that Use Binary Fission**: Binary fission is most commonly observed in:
- **Bacteria**: They reproduce by binary fission, leading to rapid population growth.
- **Protozoa**: Many protozoans also reproduce through binary fission.

5. **Evaluating the Options**: The options provided likely include various groups of organisms. Based on the understanding of binary fission:
- Bacterial protozoa (Option A) are known to reproduce by binary fission.
- Other options such as vertebrates, primates, and humans do not reproduce asexually through binary fission.

6. **Conclusion**: The correct answer to the question is that binary fission is commonly seen in **bacterial protozoa**.

**Final Answer**: Binary fission is common among **bacterial protozoa** (Option A).

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