Question

In single celled organisms diffusion is sufficient to meet all their requipment of food exchange of gases excertion of waste but this not in case of multi
cellular organisms explain the reason for this difference​

Answer 1

Answer:

Diffusion is a very slow process. If multicellular organisms used diffusion to meet all requirements of food, exchange of gases or removal of wastes it would take too much of time for carrying even a single particle in the body of the organism and hence diffusion is a process only for unicellular organisms.

Answer 2

Answer:

In single celled organisms surface area to volume ratio is optimum for diffusion/exchange of substances between the cell and its exterior and this rate of exchange suffices the requirement of a unicellular organism. However, in multicellular organisms the surface area to volume ratio is low, the exchange that takes place with the exterior or the environment occurs only through the body surface with the help of a specific structure/organ, example (Skin),However, this exchange does not compensate for millions of cells in a multicellular organism, which have distinct requirements based on their functions

Explanation:

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