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 (HEM-o-roids), sometimes called piles, are enlarged veins in the rectum, which is the lower portion of the digestive tract. They are similar to varicose veins of the legs. Hemorrhoids may bleed and cause pain.ain during bowel movements and blood in the stool are the usual symptoms that accompany hemorrhoids. Sometimes there is a discharge of mucus, and there may also be itching, burning, or pain in the area. The enlarged vein in the rectum sometimes develops a clot, which can be very painful.