Animal Kingdom Biology Quiz for NEET

Aschelminthes are pseudocoelomates and platyhelminthes are acoelomates.

Adult echinoderms are bilaterally symmetrical.

Metamorphosis refers to transformation of larva into adult. Animal that perform metamorphosis are said to have indirect development. In earthworm development is direct which means no larval stage and hence no metamorphosis.

Choanocytes (collar cells) form lining of spongocoel in poriferans (sponges). Flagella in collar cells provide circulation to water in water canal system.

Pharyngeal gill slits are present in hemichordates as well as in chordates. Notochord is present in chordates only. Ventral tubular nerve cord is characteristic feature of non-chordates.

Parapodia are present in aquatic annelids like Nereis and helps in swimming.

In coelenterates, metagenesis is alternation of generation between polyp and medusa. Polyp reproduces asexually by budding to form medusa and medusa reproduces sexually to form polyp.

In poriferans, the body is loose aggregate of cells (meshwork of cells). Internal cavities and canals are lined with food filtering flagellated cells i.e. choanocyte/collar cell. Choanocytes help in filter feeding.

Echinoderms, ctenophores and cephalochordates are exclusively marine.

Prawn, Scorpion and Locusta all belong to phylum arthropoda.

Organisms having single opening to outside that serves both mouth as well as anus have incomplete digestive system.

• Fasciola – incomplete digestive system (Platyhelminthes)
• Octopus – (Mollusca) complete digestive system
• Asterias – (Echinodermata) complete digestive system
• Ascidia – (Urochordata) complete digestive system

Triploblastic refers to organisms having three germ layers- ectoderm, mesoderm and endoderm.

(1) Corals (Cnidarians) – Diploblastic organisms

(2) Flatworms (Platyhelminthes) – Triploblastic

(3) Sponges (Porifera) – Diploblastic

(4) Ctenophores – Diploblastic

Flatworms are acoelomates (not coelomates) Roundworms/Aschemlminthes are pseudocoelomates  Molluscs are schizocoelomates (not acoelomates) Insects are schizocoelomates (not pseudocoelomates

Ascaris belong to phylum Aschelminthes. Aschelminthes are pseudocoelomate i.e. false coelom is present and have unsegmented body. Thus, metamerism is absent in Ascaris.

Annelida phylum belong to non-chordate hence have ventral nerve cord. Annelid possesses closed circulatory system and true segmentation. Annelid possess true coelom hence are eucoelomate. Annelids are not pseudocoelomate

Pinctada (Pearl oyster) is famous for pearl formation.

Metameric segmentation (true segmentation) is characteristic feature of Annelid and arthropoda. Body of arthropods is segmented.

Presence of cnidoblast is characteristic feature of cnidaria. Ctenoplana and Beroe belong to phylum Ctenophora. Ctenophores are radially symmetrical and cnidoblast cells are absent.

Centipede, Cockroach and Crab belong to Arthropoda. Arthropodes bear jointed legs and have chitinous exoskeleton.

Animals belonging to phylum porifera are mostly marines but some members live in fresh water also e.g. Spongilla (fresh water sponge).

Ctenophores reproduce exclusively by sexual means only but sponges, cnidarians and protozoans undergo asexual means of reproduction also (fragmentation, budding, fission respectively)