Experts please answer fast...

Dear Student
Cell is called as the structural and functional unit of the living organism because it the smallest living entity that is capable of an independent existence. Separated cell organelles cannot be said to be living and are not capable of independent existence. Even semi-autonomous cell organelles such as the mitochondria are not capable of independent existence, that is why they are not refered to as the 'structural and functional unit of life'.

This can be proved by performing a small activity. Observe a unicellular organism like amoeba. You will be able to see that amoeba is capable of independent existence. Anything less than a complete structure of a cell does not ensure independent. so it can be said that cell is the basic structural unit of life.
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