Animal Kingdom - Notes | Class 11 | Part 6: Aschelminthes

Cell Cycle and Cell Division - Meiosis

Phylum Aschelminthes (Roundworms): General Characters

  • Grades of Organization: Organ system.
  • Symmetry: Bilateral symmetry.
  • Germ Layers: Triploblastic.
  • Coelom: Pseudocoelomate.
  • Habit and Habitat: Aquatic and terrestrial. Free living or parasitic in plants & animals.
  • Digestive System: Complete. Tubular alimentary canal with well-developed muscular pharynx.
  • Respiratory System: Absent
  • Circulatory System: Absent
  • Reproduction:
    • Dioecious (Sexes are separate).
    • Sexual reproduction.
    • Internal fertilization.
    • Development is direct or indirect.

  • Unique Features:
    • Body is circular in cross section.
    • An excretory tube to remove body waste through excretory pore.
    • Male and female are distinct. Females are longer than males.
  • Examples:
    • Ascaris (Roundworm)
    • Ancylostoma (Hookworm)
    • Wuchereria (Filarial worm).
Aschelminthes Example
Post a Comment (0)