Theory:

Phylum Annelida:
  • These are triploblastic animals with a true body cavity.
  • They have a body that is segmented from head to tail.
  • They are mostly hermaphrodites (Both bisexual and unisexual).
  • They have locomotory structures known as parapodia for locomotion.
Phylum-Annelida-Diagram.jpg
Phylum Annelida
Phylum Arthropoda:
  • This is a phylum that consists of the largest group of animals.
  • These triploblastic animals that have a segmented body.
  • Their body has a thick chitinous cuticle which forms an exoskeleton.
  • They have jointed legs. Hence they are known as arthropods as the term arthropod means jointed legs.
  • They are unisexual and show sexual dimorphism.
45902849942_445fa8221c_c.jpg
Phylum Arthropoda
Phylum Mollusca:
  • These are triploblastic soft bodied animals.
  • The body of these animals is unsegmented.
  • These organisms have a muscular head, foot and a visceral mass, a mantle and a calcareousshell.
  • They have sexual mode of reproduction.
512px-Pulmonata_various_examples_3.jpg
Phylum Mollusa
Phylum Echinodermata:
  • These are exclusively marine triploblastic animals.
  • Their body is covered with spines and spicules.
  • Their body lacks segmentation and definite organs
  • They use water vascular system for the transport of food, gases and water throughout their body.
  • Locomotion and feeding is through tube feet.
  • They undergo sexual mode of reproduction.
Echinodermata.png
Phylum Echinodermata
Reference:
https://en.wikipedia.org/wiki/Echinoderm#/media/File:Echinodermata.png
https://www.flickr.com/photos/nmbeinvertebrata/45902849942/in/photostream/
https://upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Pulmonata_various_examples_3.jpg/512px-Pulmonata_various_examples_3.jpg
https://upload.wikimedia.org/wikipedia/commons/a/a1/Phylum-Annelida-Diagram.jpg