Why is diffusion insufficient to meet the oxygen requirements of multi-
cellular organisms like humans?
Answers
Division is insufficient to meet the oxygen requirements in a multicellular organisms because most of the cells are not exposed to the environment and the oxygen which comes into the body of multicellular organisms by diffusion is not enough to satisfy their needs.
So, multicellular organisms can't choose the method of diffusion for gas exchange as it is insufficient, so they have specific organs for gaseous exchange in their body.
In multicellular organisms like human beings diffusion is insufficient to meet the oxygen requirements of the body because of the following reasons :
• Diffusion is a very very slow process. Thus it can't fulfil the requirements of our body.
• The oxygen in human beings will have to travel last distances inside our body to reach each and every part of the cells.
• The volume of human body is so big that oxygen cannot diffuse into all the internal cells of the human body quickly.
• Also this is the reason for why the respiratory pigments are present in multicellular organisms also.