Question

why is diffusion insufficient to meet the oxygen requirements of multicellular organisms like humans?​

Answer 1

Because diffusion is a slow process

Answer 2

Diffusion is insufficient to meet the oxygen requirement of multicellular organisms like humans because in the multicellular organisms all the cells not be in direct contact with the surrounding environment . Therefore, the diffusion is insufficient to meet the oxygen requirement in them . Instead , they need specialised cell organs for breathing and exchange of gases .

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