Earthworms do not have any respiratory organs because

A. they do not need them

B. they are burrowing in habit

C. there is no sufficient space for such organs

D. the surface acts as an absorptive area which is larger than the volume

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  1. The coelomic fluid in earthworm escapes through
  2. Blood glands in Earthworm are associated with
  3. Chetae are totally absent in
  4. Nephrostomes are found in
  5. Pheretima is
  6. The enteronephric nephridia in earthworm are
  7. The fertilization in earthworms occurs in
  8. The terminal nephridial ducts of the septal nephridia of Pheretima open into
  9. The number of segments in leech is
  10. Which region in earthworm is the forest of nephridia ?
  11. Nereis is commonly called
  12. The septal and pharyngeal nephridia open into the alimentary canal and are of enteronephric type. It…
  13. The direction of blood flow in the dorsal vessel of earthworm is
  14. Spermathecae in earthworm represent
  15. In the blood vascular system of earthworm there are four pairs of hearts present in the first 13 segments.…
  16. The cliteilum singulum in earthworm is formed by
  17. Structure typically represented in every segment of earthworm is
  18. Earthworm has no skeleton but during burrowing, the anterior end becomes turgid and acts as a hydraulic…
  19. A chitinous lining in earthworm is found in
  20. The dorsal blood vessel in earthworm is
  21. Totally marine annelids belong to the
  22. A skeleton like function during locomotion of Pheretima is performed by
  23. Haemoglobin is dissolved in plasma is
  24. Annelids show advancement over the nematoda in having
  25. In earthworm, the circular muscles are highly developed in
  26. In earthworm, the first segment in which mouth is situated is known as
  27. Which of the following statements is correct ?
  28. In earthworm, the genital papillae are situated ventrally on segments
  29. In earthworm, the nephridia without neprostomes are
  30. The nitrogenous waste in earthworm consist of about