The colors will be the following: purple, dark purple, blue-black, then finally, black. Diffusion is known to be important to organisms because this is the process by which different molecules can provide the nutrients needed by the body. It is also through diffusion that the different waste products from the body can be removed.
This is important because if the body would not be able to remove wastes, then it will have a harder time to cleanse the body from toxins that the body does not need. It should be remembered that diffusion and osmosis are different from each other but they are both needed by the body.