Answer:
Cells are the simplest structure to fit all of the characteristics necessary to be considered alive.
Step-by-step explanation:
The cell (from the Latin cellula, diminutive of cella, ‘hollow’) 1 is the morphological and functional unit of every living being. In fact, the cell is the smallest element that can be considered alive.2 In this way, living organisms can be classified according to the number of cells they possess: if they only have one, they are called unicellular (such as protozoa or bacteria, microscopic organisms); If they have more, they are called multicellular. In the latter the number of cells is variable: from a few hundred, as in some nematodes, to hundreds of billions (1014), as in the case of the human being. The cells usually have a size of 10 µm and a mass of 1 ng, although there are much larger cells.