For instance, it can cause liver enlargement, it can cause damage to our liver, and that eventually might actually progress to cirrhosis. And cirrhosis is basically a very advanced form of liver damage. It can also cause, cause cataract formation, delayed mental development, ovarian failure, and a feeling of laziness or lack of enthusiasm and so forth. So what I'd like to focus on in this lecture is cataract formation. So how does the build up of the galactos actually lead to cataract formation? Well, what exactly is a cataract?