Question

Diffusion is sufficient in single cellular but not in multicellular

Answer 1

the answer of your question is:
TRUE





hope it works

Answer 2

Yes because in single cellular organisms their full body is in contact with environment.. so diffusion alone is sufficient for them.. but for multicelluear organisms their all parts of body are not in direct contact with enviroment..so Diffusion is sufficient in single cellular but not in multicellular