Question

1. According to animal classification, which of the following group of animals is correct ? (1) Euplectella, Spongilla, Sycon (2) Nereis, Earthworm, Starfish (3) Octopus, Starfish, Jellyfish (4) Hirudinaria, Unio, Antedon​

Answer 1

Answer:

Hydra is a genus that belongs to the phylum Cnidaria and has radial symmetry.

Taenia (Tapeworm) is bilaterally symmetrical, whereas Octopus is radially symmetrical.

Sharks (Carcharodon) have bilateral symmetry.

Aurelia (Jellyfish) possesses radial symmetry. Jellyfish is a marine animal that belongs to the phylum Cnidaria, whereas Asterias (starfish) belong to Echinodermata and shows radial symmetry at the adult stage.

Therefore, the correct answer is option D.

Answer 2

According to animal classification (3) Octopus, Starfish, Jellyfish is the correct answer

Explanation:

Euplectella, Spongilla, Sycon:

• The Venus's-flower-basket belongs to the Hyalosponges genus, which has a skeleton of interwoven siliceous spicules and grows in the shape of a cornucopia.

Nereis, Earthworm, Starfish:

• Nereis is a polychaete worm genus in the Nereididae family. It contains a large number of species, the most of which are marine. For locomotion, Nereis have setae and parapodia.
• They may have two different forms of setae on their parapodia. Support is provided by acicular setae.

Octopus, Starfish, Jellyfish:

• Octopuses are soft-bodied, eight-limbed mollusks that belong to the Octopoda order.
• Squids, cuttlefish, and nautiloids are all members of the Cephalopoda class, which includes over 300 species.

Hirudinaria, Unio, Antedon​:

• The Indian leech Hirudinaria granulosa can be found in freshwater tanks, ponds, lakes, swamps, and slow streams.
• It favours shallow water and hides among weeds, logs, and stones.