Animal Kingdom - Notes | Class 11 | Part 7: Annelida

4. ANIMAL KINGDOM

PHYLUM ANNELIDA (SEGMENTED / RINGED WORMS): GENERAL CHARACTERS

1. Grades of organization:
• Organ system.
2. Symmetry:
• Bilateral symmetry.
3. Germ layers:
• Triploblastic.
4. Coelom:
• Coelomate.
5. Habit and habitat:
• Terrestrial, fresh water or marine. Free living or parasitic.
6. Digestive system:
• Complete.
7. Respiratory system:
• Cutaneous respiration. Some have branchial (gill) respiration.
8. Circulatory system:
• Closed type.
9. Reproduction:
• Sexual.
• Earthworms & leeches are monoecious.
• Neries is dioecious.
• Development is direct or indirect.
10. Unique features:
• Segmentation like rings.
• Longitudinal and circular muscles help in locomotion.
• Locomotory organs are setae (in earthworm) or parapodia (in Neries).
• Excretion by Nephridia.
• Paired ganglia connected by lateral nerves to a double ventral nerve cord.
11. Examples:
• Pheretima (earthworm)
• Hirudinaria (blood sucking Leech)
• Neries (aquatic. Parapodia for swimming).

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👇 Select Your Topic Here 👇

• Topic 1: Basis of Classification
• Topic 2: Porifera
• Topic 3: Cnidaria
• Topic 4: Ctenophora
• Topic 5: Platyhelminthes
• Topic 6: Aschelminthes
• Topic 7: Annelida
• Topic 8: Arthropoda
• Topic 9: Mollusca
• Topic 10: Echinodermata
• Topic 11: Hemichordata
• Topic 12: Chordata - up to Sub phylum Vertebrata
• Topic 13: Chordata - Cyclostomata, Pisces
• Topic 14: Chordata - Tetrapoda