Where does the matter in the body of an animal come from?

All eukaryotic cells contain small bodies called

The small molecule cyclic amp (camp) takes about 0.2 second to diffuse 10 μm, on average, in a cell. suppose that camp is produced near the plasma membrane on one end of the cell; how long will it take for this camp to diffuse through the cytosol and reach the opposite end of a very large cell, on average? assume that the cell is 200 μm in diameter.

Has anyone taken the genetics unit test in connexus? not looking for answers, just a little bit what to expect and some with studying.