Animal Kingdom Question 734

Question: Hydra recognises its prey by

[BVP 2001; MH CET 2003]

Options:

A) Nematocyst

B) Chemical stimulus

C) Smell

D) Sensitivity

Show Answer

Answer:

Correct Answer: A

Solution:

In Hydra, there are nematocyst which are minute, elongated or spherical capsule. Several capsules occur on the body surface.

Each is produced by a special cell called a cnidoblast and contains a coiled, hollow, usually barbed thread, which quickly turns outward from the capsule upon proper stimulation.

The purpose of the thread is to ward off enemies or to capture prey. The thread contains poison which helps to capture the prey.

Thus, the correct answer is option A.