List the types of substances that most readily diffuse through a cell membrane

A substance is a pure form of matter that contains only one type of atom or molecule. It can be further divided into two sub-categories: elements and compounds. The types of substances that most readily diffuse through a cell membrane, however, are the nonpolar and small polar molecules like carbon dioxide and oxygen. These two molecules simple diffusion of water through the membrane thru a process known as osmosis.