The members of which phylum are commonly known as sponges?

The correct answer is ​Porifera.

Key Points

• Phylum Porifera:
  • Members of the phylum Porifera are commonly known as sponges. Hence, Option 1 is correct.
  • They are mostly marine, and asymmetrical animals, but few are freshwater animals.
  • Spongilla is a freshwater sponge.
  • All animals of this group are found in water and bear pores in the body. 
  • These are multicellular animals but cells do not make regular tissues.
  • Numerous pores are known as Ostia found on the body wall. Hence, they are called sponges.
  • Skeleton is made up of minute calcareous or silicon spicules.
  • Examples: Sycon, Sponge, etc.

 Additional Information

• Phylum Coelenterata:
  • This phylum is also known as Cnidaria.
  • Animals are aquatic and diploblastic.
  • Around the mouth, some threadlike structures are found known as tentacles.
  • The body has radial symmetry.
  • Specialized cnidoblast cells are found which help in catching the food.
  • Example: Hydra, Jellyfish.
• Phylum Annelida:
  • The body is long, thin, soft, and metamerically segmented.
  • Locomotion takes place through Setae made up of Chitin.
  • The alimentary canal is well developed.
  • The nervous system is normal and blood is red.
  • Excretion by nephridia.
  • Both unisexual and bisexual.
  • Example: Earthworm.
• Ctenophora is also known as comb jellies.
  • It comes under the phylum Invertebrates.