Thu March 03, 2011 By: Aishanikhanna

why is coelom absent in diploblastic organisms?

Expert Reply
Fri March 04, 2011
Dear student,
In triploblastic animals, the 3 germ layers are ectoderm, mesoderm and endoderm, the mesoderm being the middle layer. However in diploblastic animals, only the ectoderm and endoderm are present.
The true body cavity or coelom originates from the mesoderm and since this layer is absent in diploblastic animals, they lack coelom.
Regards, Team Topperlearning
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