Question

Why is diffusion insufficient to meet the oxygen requriements of multi cellular oranisms like humans?

Answer 1

Because in unicellular organisms the whole body is in contact with the outer environment but it is not the case in humans because they have high energy requirements simple diffusion is not sufficient as all our cells and tissues need energy
If simple diffusion would have taken place in humans then to transport the blood from heart to toes it would have taken 3 years this is a fact

Answer 2

HEYMATE!!!!

■ In multi - cellular organisms, all the cells may not be in direct contact with the surrounding environment.

■thus,simple diffusion will not meet the requirements of all the cells.

■In case of a single - celled organism, no specific organs for taking in food, exchange of gases or removal of wastes may be needed because the entire surface of the organism is in contact with the surrounding environment.

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