Colon lining. Light micrograph of a section through a human colon showing the mucosal glands (small purple ovals). The entire colon is lined with tubular mucosa glands. Each gland contains two types of cell. The goblet cells (light purple) secrete a lubricant into the colon which aids the movement of faeces. They are surrounded by a layer of absorptive cells (dark purple) which absorb water from the gut contents. The number and shape of the glands greatly increases the surface area for absorption. The glands are supported on a sheet of smooth muscle (the muscularis mucosae, pink and white). Haematoxylin and eosin stain. Magnification: x5 at 35mm size.