Question

Planarians lack dedicated respiratory and circulatory systems. this deficiency does not cause a problem because ________. planarians lack dedicated respiratory and circulatory systems. this deficiency does not cause a problem because ________. they lack mesoderm as embryos and, therefore, lack the adult tissues derived from mesoderm their body cavity, a pseudocoelom, carries out these functions their flame bulbs can carry out respiratory and circulatory functions none of their cells are far removed from the gastrovascular cavity or from the external environment

Answer 1

respiratory and circulatory system

Answer 2

I think the deficiency of dedicated respiratory and circulatory systems in Planarians does not cause a problem because none of their cells are far removed from the gastrovascular cavity or from the external environment. Planarians are free-living flatworms and form the class Turbellarians in the Phylum Platyhelminthes. Flatworms have three tissue layers, that is the ectoderm, mesoderm, and endoderm.