Explain the feeding mechanism in hydra.

Explanation

### Step-by-Step Solution:

1. **Structure of Hydra**: Hydra is a small, tubular, freshwater organism that has a simple body structure. It has a central mouth surrounded by tentacle-like projections.

2. **Tentacles and Nidoblast Cells**: The finger-like projections around the mouth are called tentacles. These tentacles contain specialized cells known as nidoblasts (or cnidocytes).

3. **Function of Nidoblasts**: Nidoblast cells contain stinging structures called nematocysts, which are capable of injecting toxins into prey. These toxins can paralyze or kill small organisms that come into contact with the tentacles.

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