“Comprehensive Notes on Animal Kingdom – Class 12 Biology”

Class 11 Botany – Animal Kingdom Notes

Prepared by: Rohit Gulia sir physics walla dwarka mor


1. Basis of Classification

• Levels of Organization

• Cellular (Porifera)

• Tissue (Cnidaria, Ctenophora)

• Organ (Platyhelminthes, Nematoda)

• Organ system (Annelida onwards)

• Symmetry

• Asymmetrical: Porifera

• Radial: Cnidaria, Echinodermata (adult)

• Bilateral: Platyhelminthes onwards

• Germ Layers

• Diploblastic: Cnidaria

• Triploblastic: Platyhelminthes onwards

• Coelom

• Acoelomate: Platyhelminthes

• Pseudocoelomate: Nematoda

• Coelomate: Annelida onwards

• Segmentation & Notochord

• Segmented: Annelida, Arthropoda, Chordata

• Notochord present: Chordata

2. Non-Chordates

Porifera (Sponges)

, • Cellular level organization

• Asymmetrical

• Aquatic, mostly marine

• Digestion: Intracellular

• Skeleton: Spicules

• Examples: Spongilla, Sycon

Cnidaria (Hydra, Jellyfish)

• Tissue-level organization

• Radial symmetry

• Diploblastic (Ectoderm + Endoderm)

• Cnidoblasts for defense

• Examples: Hydra, Obelia

Ctenophora (Comb Jellies)

• Tissue organization

• Radial symmetry

• Bioluminescent

• Example: Pleurobrachia

Platyhelminthes (Flatworms)

• Triploblastic, acoelomate

• Bilateral symmetry

• Some parasitic

• Examples: Fasciola, Taenia

Nematoda (Roundworms)

• Pseudocoelomate, unsegmented

• Bilateral symmetry

• Mostly parasitic