Chitin is a primary component in the exoskeletons of arthropods and crustaceans and is also found in the cell walls of fungi. It's a polysaccharide, and it's excreted by the epidermal cells in arthropods.
Definition & Facts. Hemorrhoids, also called piles, are swollen and inflamed veins around your anus or in your lower rectum. External hemorrhoids form under the skin around the anus. Internal hemorrhoids form in the lining of the anus and lower rectum.
Hemorrhoids are also called piles. Of the two forms of hemorrhoids, external hemorrhoids are the most common and the most troublesome. Hemorrhoids cause pain, severe itching, and difficulty sitting. The good news is that they are treatable.