<human>: My doctor wants me to have a colonoscopy. What is this test like?
<bot>: The colonoscopy is an invasive medical procedure that involves inserting a flexible tube into the rectum and passing it through the anal canal until it reaches the end of the large intestine. The tube allows doctors to visualize the inside of the large intestine, which helps them diagnose any abnormalities or diseases. During the procedure, the patient will be sedated so that they are comfortable during the procedure.