Internal analsphincters are smooth muscle and are involuntary, external anal sphincters areskeletal muscle and are voluntary. Functions tostart enzymatic catabolism of complex starches and other carbohydrates intosmaller carbohydrates and disaccharides.
Amylase is a carbohydrase.
Thehydrogen ion is actively transported across the cell membrane to the stomachlumen. Stomach lumen attains a pH of 2. Were the stomach to produce active pepsin in its cytoplasm, thecell would be harmed. Pepsin is a protease and acts to chemically digestproteins to amino acids. Secreted by the stomach and cellsof the small intestine, lipase degrades lipids into fatty acids.