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 normal veins around the anus or lower rectum that can become swollen, causing pain, itchiness and sometimes bleeding. Hemorrhoids are usually temporary and are not dangerous. About 75% of people will have a hemorrhoid at some time in their lives.