3 Answers
Cells are the basic units of life capable of doing all the required biochemical processes that a normal cell has to do in order to live. The basic needs for the survival of all living organisms are the same. All living organisms need to respire, digest food for obtaining energy, and get rid of metabolic wastes.
Cells are capable of performing all the metabolic functions of the body. Hence, cells are called the functional units of life.
Unicellular organisms are capable of independent existence and they can perform the essential functions of life. Anything less than a complete cell does not ensure independent living. Hence, cell is called the fundamental structural and functional unit of life.
Every cell in an organism carries out all the biological activities independently. It releases energy by the breaking of food molecules. With this energy cell synthesizes complex molecules. Cells also play a major role in heredity. In plants, cells carry out photosynthesis. Each cell reproduces itself and has its own life cycle. The cell also regulates and maintains its own activities. So cell is considered a basic unit of life.