Final answer:
A water enema or Fleet's solution is given to clear the colon for a colonoscopy, which allows examination of the entire colon and rectum to ensure proper visibility during the procedure.
Step-by-step explanation:
A water enema or Fleet's solution is often used as a bowel preparation for procedures that require a clear field of vision in the large intestine. The procedure that requires this type of preparation in the morning before it is conducted is a colonoscopy. During a colonoscopy, a doctor uses a flexible tube with a camera to view the lining of the colon and rectum. By contrast, a sigmoidoscopy examines only the lower part of the colon (sigmoid colon), and an upper endoscopy examines the esophagus, stomach, and small intestine. A barium enema also visualizes the colon but involves the use of a barium contrast dye, not a water enema.
The colon's primary function is the absorption of water from the chyme, turning it into semi-solid feces or stool that's stored in the rectum until excreted. This normal digestive process is important for understanding why bowel preparation is necessary. For a clear visual inspection during a colonoscopy, the colon must be free from any stool, which is achieved by using a preparation like a water enema.