Animal Kingdom Question 155
Question: Assertion : Nematocysts are present in coelenterates. Reason : Nematocysts are specialized cells.
Options:
A) If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B) If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C) If the assertion is true but the reason is false
D) If both the assertion and reason are false
Show Answer
Answer:
Correct Answer: C
Solution:
One of the most characteristic structure of all coelenterates are the stinging cells, called nematocysts.
These are not cells but cell organelles found in specialized cells called cnidocytes or cnidoblasts.
These develop from modified interstitial cells of epidermis and are not found in gastrodermis.
The cnidoblasts act as organs for offence and defence.
They also serve for locomotion, food capture and anchorage.
Nematocysts occur on oral arms, ex-and sub-umbrellar surface, marginal tentacles as well as gastric filaments.
Above 30 different kinds of nematocysts are found in cnidarians.
BETA
