Question: what is the key difference between a coelom and a pseudocoelom?
Answer: Pseudocoelom refers to the false body cavity. It is filled with fluid and the members of protostomes are known to be pseudocoelomate in nature. Blastocolemomate is another term for pseudocoelomate. The absence or negligible mesodermal lining distinguishes the pseudocoelom from the true coelom.