The Euclidean plane is a flat, infinitely large two-dimensional space following the rules of two-dimensional Euclidean geometry. It can be formed from the Cartesian product of two copies of the Euclidean line. A plane can be used to bisect a cell, and cells can have planes of symmetry through which they are reflected. The place at which a cell intersects a plane gives a two-dimensional shape and the change in shape as the cell passes through the plane can give information about the structure of the cell.