Animal Kingdom - Notes | Class 11 | Part 8: Arthropoda

4. ANIMAL KINGDOM

PHYLUM ARTHROPODA (JOINT-LEGGED ANIMALS): GENERAL CHARACTERS

Arthropoda is the largest phylum. Over two-thirds of all named species are arthropods.

1. Grades of organization:
• Organ system.
2. Symmetry:
• Bilateral symmetry.
3. Germ layers:
• Triploblastic.
4. Coelom:
• Coelomate.
5. Habit and habitat:       
• Cosmopolitan.
6. Digestive system:          
• Complete.
7. Respiratory system:
• Gills/ book gills/ trachea/book lungs.
8. Circulatory system:
• Open type.
9. Reproduction:
• Mostly dioecious.
• Usually internal fertilization.
• Mostly oviparous.
• Development is direct or indirect.
10. Unique features:
• Jointed appendages.
• Body has 3 regions: head, thorax & abdomen.
• Body is covered by chitinous cuticle (exoskeleton).
• Excretion by Malpighian tubules.
• Sensory organs are antennae, compound & simple eyes, statocysts (balance organs).
11. Examples:
• Spider, Scorpion, Crab, Prawn, Insects etc.
• Economically important insects: Apis, Bombyx, Laccifer.
• Vectors: Mosquitoes (Anopheles, Culex & Aedes), Housefly etc.
• Gregarious pest: Locusta.
• Living fossil: Limulus (King crab).

============

👇 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