Comb Jellies

14.11.2024

Comb Jellies

Why in the news?      

            Comb jellies, also known as ctenophore Mnemiopsis leidyi, can defy age and revert to younger versions of themselves, according to a study published recently.

About Comb Jellies:

• They are transparent, gelatinous invertebrates that drift through the waters of our global ocean.
• They are one of the oldest multicellular phyla in the animal kingdom, probably existing already for more than 500 million years.
• There are between 100 and 150 known species of comb jellies, the best known of which are found close to shore.

Description of Comb Jellies:

• They are colorful, simple invertebrates that are part of the family Ctenophora.
• Each species varies in length, but the average size of a comb jelly is about four inches long.
• Comb jellies get their name from their eight rows of plates made of fused cilia (little hairs) that they use to move through the water, which looks like combs.
• They are the largest animals known to use cilia for locomotion.
• They have two large, trailing tentacles that branch out to create the appearance of a net-like structure of many tentacles.
• These organs serve as sticky fishing lines, which they use to trap and move prey to their bodies.
• These animals have two major cell layers, the external epidermis and internal gastrodermis; in between these cell layers is the mesoderm which is what gives the animals their gelatinous appearance.
• Many species are bioluminescent, meaning they can use proteins in their bodies to create an ethereal blue or green glow in response to stimuli like touch.
• Comb jellies are carnivorous and opportunistic, feeding on whatever passes them by.
• Unlike their close relatives, the jellyfish, comb jellies do not have stinging tentacles and are harmless to humans.

                                                                 Source: Indian Express

Consider the following statements regarding Comb Jellies:

Statement-I:They are transparent, gelatinous invertebrates that drift through the waters.

Statement-II:They have stinging tentacles and are highly poisonous.

Which one of the following is correct in respect of the above statements?

A.Both Statement-I and Statement-II are correct, and Statement-II is the correct explanation for Statement-I.

B.Both Statement-I and Statement-II are correct, and Statement-II is not the correct explanation for Statement-I.

C.Statement-I is correct, but Statement-II is incorrect.

D.Statement-I is incorrect, but Statement-II is correct.

Answer C