The size of the cells depends on their area and volume, and the shape has a model according to its function. Form and function are determined through genes.
According to Spencer’s law, the cell volume grows faster than the area, since the increase in volume is proportional to the cube of the linear dimensions and the growth of the surface is proportional to the square of the dimensions.
This disproportionate relationship due to growth incites serious problems of sustenance and gas exchange between the cell and the external environment.
If a cell increases in size 10 times its volume will be a thousand times greater and consequently the need for supply and oxygen to maintain its structural balance will increase a thousand times.
If the surface has grown only one hundred times, automatically its food and oxygen gathering power will only increase one hundred times.
The form and function of the cell
Each cell has a template according to its function, and thus form and function are conferred through genes.
The shape is influenced by several external factors, such as pressure from other cells that make them flat. In plants it has an angular shape, in animals the cells are devoid of cell walls and are more wavy.