ABSTRACT
The wall of the colon is divided into four layers: the serosa, external muscular region (muscularis externa), submucosa and mucosa (Figure 7.2). The squamous epithelium of the serosa is covered with adipose tissue which forms distended fat pouches of peritoneum, known as appendices epiploicae. These are larger and more numerous in the distal half of the colon and are one of its distinguishing features. The serosa is absent from the rectum and anal canal.
