All organisms are composed of cells. Cells are the fundamental unit of life. There are unicellular organisms (who have only a single cell). Human beings and most other animals are multi cellular animals. The cells function similarly in all living organisms, whether they are unicellular or composed of many cells. The details of the cells of all living organisms are visible only through a microscope.
The system in multi cellular organisms perform the same functions as the cells, that is supporting the transportation of materials, breaking down the sugar to form energy to form carbon dioxide, which is abbreviated as CO2 and water, which is produced by the process of respiration. The only difference between the cells of a unicellular organism, such as an amoeba, and the cells of a multi cellular organism is that unlike the cell of an amoeba and other unicellular organism, the cells of a multi cellular organism can multiply and the process of cell reproduction can take place.
The system in multi cellular organisms perform the same functions as the cells, that is supporting the transportation of materials, breaking down the sugar to form energy to form carbon dioxide, which is abbreviated as CO2 and water, which is produced by the process of respiration. The only difference between the cells of a unicellular organism, such as an amoeba, and the cells of a multi cellular organism is that unlike the cell of an amoeba and other unicellular organism, the cells of a multi cellular organism can multiply and the process of cell reproduction can take place.