In which of the following organism, asexual reproduction occurs by buds?

Options

A. Chlamydomonas
B. Hydra
C. Penicillium
D. Sponge

Answer

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

1. **Understanding Asexual Reproduction**: Asexual reproduction is a mode of reproduction that does not involve the fusion of gametes. It often involves processes such as budding, fragmentation, or spore formation.

2. **Analyzing the Options**:
- **Option 1: Chlamydomonas**: This organism primarily reproduces asexually through the formation of zoospores, which are flagellated spores. Therefore, this option is incorrect for budding.

- **Option 2: Hydra**: Hydra is known for asexual reproduction through budding. In this process, a small outgrowth (bud) forms on the parent organism, which eventually detaches and grows into a new individual. This option is correct.

- **Option 3: Planaria**: Planaria reproduce asexually through a process called fission, where the organism splits into two or more parts, each capable of regenerating into a complete organism. This option is incorrect for budding.

- **Option 4: Sponge**: Sponges can reproduce both asexually and sexually, but their asexual reproduction does not typically involve budding in the same way as Hydra. Instead, they may reproduce through fragmentation or by producing gemmules. Therefore, this option is also incorrect for budding.

3. **Conclusion**: After analyzing all the options, the organism that reproduces asexually by budding is **Hydra**.

**Final Answer**: Hydra

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