Question

1) why is diffusion insufficient to meet the oxygen requirement of multicellular organism like humans?
2) what criteria do we use to decide whether something is alive ??
3) what are outside raw materials used for by an organism ?
4) what processes would you consider essential for maintaining life ?
please help me to solve this question
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Answer 1

1.Diffusion is insufficient to meet the O2 requirements in humans because the respiratory organs in human body is present inside the body thus Human body needs a special passage i.e. the Respiratory System fir the entrance of Oxygen .

2.We use many criteria ti determine something as living or non living.

a-The motion in body

b-Growth

c-Locomotion

and many more....