Final answer:
The main actions in the Large Intestine involve peristalsis, water absorption, and bacterial breakdown of carbohydrates. Mechanical movements such as haustral contractions and mass movements help in processing waste, while mucus from goblet cells facilitates fecal passage.
Step-by-step explanation:
The main muscular and chemical actions involved in the Large Intestine (Colon) are peristalsis and water absorption. Mechanical digestion in the large intestine includes sluggish segmentation known as haustral contractions, peristalsis, which progresses slowly compared to earlier sections of the alimentary canal, and mass movements that propel contents toward the rectum.
Chemical digestion is carried out by bacteria through saccharolytic fermentation, breaking down carbohydrates that were not digested previously, resulting in the production of gases. The mucosa is lined with goblet cells that secrete mucus, aiding the passage of feces through the large intestine.