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Life Processes — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceLife Processes3 Marks
Question
Diffusion pressure cannot deliver oxygen all over the body in bigger animals’. Comment on this statement.
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Answer

This diffusion pressure plays a major role in exchange of gases in plants and in smaller animals but fails in bigger animals. Multicellular organisms such as humans possess complex body designs. They have specialised cells and tissues for performing various necessary functions of the body such as intake of food and oxygen. Unlike unicellular organisms, multicellular cells are not in direct contact with the outside environment. Therefore, diffusion cannot meet their oxygen requirements.

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