The mode of digestion of food in hydra is

Options

A. only extracellular
B. only intracellular
C. atuotrophic
D. partly extracellular and partly intracellular

Answer

**Step-by-Step Solution:**

1. **Understanding Hydra's Classification**: Hydra belongs to the phylum Cnidaria, which is known for its simple body structure and primitive characteristics.

2. **Identifying the Digestion Methods**: Hydra employs two distinct modes of digestion:
- **Extracellular Digestion**: This process involves the secretion of digestive enzymes into the surrounding environment. These enzymes break down food particles outside of the Hydra's body. The organism can then engulf the digested nutrients.
- **Intracellular Digestion**: After the food particles are broken down extracellularly, some of the smaller particles can be taken into the cells of the Hydra through the process of phagocytosis, where the cell membrane engulfs the food particle.

3. **Analyzing the Options**: The question provides several options regarding the mode of digestion:
- Only extracellular digestion
- Only intracellular digestion
- Autotrophic digestion
- Partly extracellular and partly intracellular digestion

4. **Eliminating Incorrect Options**:
- The first option (only extracellular) is incorrect because Hydra also performs intracellular digestion.
- The second option (only intracellular) is incorrect for the same reason; Hydra does not rely solely on intracellular digestion.
- The third option (autotrophic) is incorrect because Hydra does not have chlorophyll and cannot perform photosynthesis.

5. **Selecting the Correct Answer**: The last option (partly extracellular and partly intracellular) is correct, as Hydra utilizes both methods of digestion.

**Final Answer**: The mode of digestion of food in Hydra is partly extracellular and partly intracellular.

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