Question

Are mollusca haemocoel or do they have reduced body cavity(reduced true coelom) or only do arthropods have true body cavity(coelom)

Answer 1

Answer:

The key difference between coelom and haemocoel is that the coelom is the principal body cavity of annelids, echinoderms and chordates that originated from the mesothelium while haemocoel is the primary body cavity of arthropods and molluscs which is a reduced form of a coelom.

Explanation:

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