So remember that proxosomes are membrane bound organelles that also contain enzymes involved in the fatty acid oxidation process. Now, what types of fatty acids do we generally oxidize and break down in our peroxisomes? Well, it's the fatty acids that contain 20 or more carbon atoms. So these are known as very long chain fatty acids or simply VLCFA. Now, what exactly the major difference between the beta oxygen process that takes place inside our mitochondria and inside proxosomes? Well, the major difference is step one of beta oxidation.