Water diffusion is called osmosis. Oxygen is a small molecule and it's nonpolar, so it easily passes through a cell membrane. Carbon dioxide, the byproduct of cell respiration, is small enough to readily diffuse out of a cell. Small uncharged lipid molecules can pass through the lipid innards of the membrane.
Answer: Precipitation I believe
Answer:
I am so sorry I just answered because I need points for my exam
Answer: Because each one of them helps other organs, cells, etc.. Because everything in your body needs to work together. For example, one of the most important functions of organ systems is to provide cells with oxygen and nutrients and to remove toxic waste products such as carbon dioxide.