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 lumps or masses of tissue in the anus, which contain enlarged blood vessels. Any increase in abdominal pressure may produce hemorrhoids. This may be from: Repeated straining to have a bowel movement, especially in people who suffer from frequent constipation.