Question

Tube feet are the locomotory organ of -
(a)Starfish
(b)Jellyfish
(c)Silverfish
(d)Scoliodon

Answer 1

Hint: Tube feet would be a required locomotory organ for an organism that needs to adhere to surfaces and absorb nutrients to supply to the rest of the body. Other classes of animals do not require tube feet as they are free moving and have other organs specifically for ingesting food.

Complete answer:
- Tube feet are a characteristic of the Phylum Echinoderm. They are a characteristic organ of the starfishes.
- They are a part of the water vascular system, which is a hydraulic system in echinoderms necessary for locomotion, food ingestion, adhesion, and gas exchange.
- The tube feet also help in suction on surfaces. They are shaped like suction cups but the actual adhesion is carried out by the adhesive chemicals present.

Additional Information: - Jellyfish, of the Cnidaria phylum, are parasitic and carnivorous in nature. They make use of their tentacles to hunt any prey and ingest food and expel waste through one mouth.
- The Silverfish is a small, silver-colored insect of the Arthropoda phylum. They are, therefore, motile. They consume any matter that contains polysaccharides like starches. Hence, they are common household pests that eat paper, glue, paint, dandruff, etc.
- Scoliodon, or sharks, belong to the phylum Chordata and are motile fish. They are predatory and carnivorous in nature and are marked by their rows of sharp teeth for food consumption and streamlined body and fins for locomotion.

So, the correct answer is ‘Starfish’.

Note: - Apart from locomotion, the tube feet act as accessory gills. The water vascular system also helps in transferring oxygen from the feet and carbon dioxide to the feet from the rest of the body.
- They also transfer nutrients from the gut to the muscles involved in locomotion.
- The digestive system of the starfish is present in most of its discs and it extends up to its arms.