In Hydra, waste materials after digestion and nitrogenous waste materials are removed from

Options

A. Mouth only
B. Body wall only
C. Mouth and body wall respectively
D. Mouth and tentacles respectively

Explanation

To answer the question about how waste materials are removed in Hydra, we can break down the information into clear steps:

### Step-by-Step Solution:

1. **Understanding Hydra's Structure**:
- Hydra is a freshwater organism that belongs to the phylum Coelenterata (now often referred to as Cnidaria). It has a simple body structure and lacks complex organ systems.

2. **Digestion Process**:
- In Hydra, food is taken in through the mouth and digested in the gastrovascular cavity (also known as the coelenteron). This cavity serves both digestive and circulatory functions.

3. **Excretion of Undigested Food**:
- After digestion, any undigested food residues are expelled from the body. This process occurs through the mouth, as Hydra does not have an anus.

4. **Nitrogenous Waste Removal**:
- Nitrogenous waste products, which are byproducts of metabolism, are removed through the body surface. Hydra lacks specialized excretory organs, so these wastes diffuse out directly through the body wall.

5. **Conclusion**:
- Therefore, the undigested food is removed from the mouth, while nitrogenous waste is removed from the body surface.

### Final Answer:
- In Hydra, waste materials after digestion are removed from the mouth, and nitrogenous waste materials are removed from the body surface.

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