Question

in unicellular organism no specific organ is used for exchange gas ( give reason)​

Answer 1

This is because there whole body is in contact with the surroundings so gases just diffuse out and they don’t need an organ for it.

Answer 2

Explanation:

if it is unicellular,it 's body is simply a cell,a cell have no organ but groups of cell make a organ example:lungs.so it take air through the cell wall.

if my exp is not much clear comment me I will give some another ans