Dear student,
Cells that can perform all the metabolic activities required for growth and sustenance of life is called an organism. Hence, cell is called the basic unit of life. Such cells come together to perform a specialised function, and are called as tissues. Many such tissues come together to perform a specialised function known as organ. And many organs come together to constitute an organism.
Therefore, organism is any living entity whether multicellular or unicellular that can perform metabolic functions for their growth and sustenance.
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