Generally prokaryotic cells and eukaryotic cells only differ in size by about a factor of 10. The upper limit to the size of a cell is largely determined by. Smaller cells in comparison to larger cells have a ratio of surface area to volume. The larger the surface area of a cell, the is the exchange of molecules across the cell boundary.

The correct answer would be - a) surface area to volume ratio

b) As the cell size increases, the surface area to volume ratio decreases

c) The higher/larger is the surface area, the more is the exchange of ions across the membrane

Explanation:

Prokaryotic cells are normally smaller than the eukaryotic cells about a factor of 10, normally the prokaryotic cells range from 0.1 to - 5 µm in diameter such while the 10 to 100 µm in diameter.

The upper limit to the size of a cell is determined by the surface area to volume ratio of the cell. Increase in the cell size the ratio of surface area to volume decreases. The higher the surface area of the cell the more is the transport or movement of the ions across the membrane.

Thus, the correct answer is - a) surface area to volume ratio

b) As the cell size increases, the surface area to volume ratio decreases

c) The higher/larger is the surface area, the more is the exchange of ions across the membrane.