Final answer:
The descending colon itself does not typically use enzymes to break down macromolecules as most digestion is completed prior to this stage. Enzymes like amylase, sucrase, lactase, and maltase break down carbohydrates, while proteases like pepsin and peptidase, and lipase enzymes break down proteins and lipids, respectively, in the digestive tract.
Step-by-step explanation:
The descending colon is a part of the large intestine where water and salts are absorbed from the material that remains after digestion and absorption in the small intestine. Typically, the descending colon does not use enzymes to break down macromolecules because most of the digestive process is completed prior to the chyme reaching the descending colon. However, in the entire digestive tract, various enzymes are used to break down different types of macromolecules. For carbohydrates, enzymes like amylase, sucrase, lactase, and maltase are responsible for breaking down complex carbohydrates into simpler sugars. Proteins are broken down by proteases such as pepsin and peptidase, as well as hydrochloric acid found in the stomach. Lipids are digested with the help of lipase enzymes. Lastly, nucleic acids such as DNA would be broken down by nucleases, not typically found in the descending colon. It is worth mentioning that the brush border enzyme dipeptidase breaks down proteins, but it acts in the small intestine instead of the descending colon.