In this article we will discuss about Phylum Annelida:- 1. Taxonomic Retrospect of Phylum Annelida 2. Definition and Fossil Record of Phylum Annelida 3. Habit and Habitat 4. Generalised Characters 5. Specialised Characters 6. Features 7. Trend in Classification 8. Phylogenetic Relationship 9. Locomotion 10. Circulatory System 11. Respiratory System 12. Reproductive System 13. Nervous System 14. Regeneration. Contents: Taxonomic [...]
List of three important members of Phylum Annelida:-1. Polychaetes 2. Oligochaetes 3. Hirudinea. Member # 1. Polychaetes: This group includes heterogeneous forms where variation is marked not only in size but also in habits and structural organisation. Following examples will illustrate the range of diversities: Arenicola: Burrows in sand; body is distinctly divisible into three regions—anterior region (or pre-branchial region) [...]
The upcoming discussion will update you about the difference between Coelom and Pseduocoelom. Difference # Coelom: 1. Fluid filled perivisceral cavity of most triploblastic animals (e.g., most annelids, echinoderms and vertebrates), situated between the body wall and gut. In arthropods and molluscs, it is not the perivisceral cavity; it forms the cavity of excretory organs and gonads and acts as [...]