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 swollen blood vessels in the rectal area. They typically range in size from as small as a pea to as large as a grape, and they can develop inside the rectum or protrude through the anus. Hemorrhoids can be itchy and mildly uncomfortable â or downright painful. Sometimes they even cause rectal bleeding, especially when you have a bowel movement. Pregnancy makes you more prone to hemorrhoids (as well as to varicose veins in the legs and sometimes even in the vulva) for several reasons. Your growing uterus puts pressure on the pelvic veins and the inferior vena cava, a large vein on the right side of the body that receives blood from the lower limbs.