The GI tract has its own nervous system that can sense food and trigger reflexes. The enteric plexus is involved in gastroileal, ileogastric, and intestino-intestinal reflexes which regulate movement and emptying of contents through the intestines. Hormones like secretin and CCK are released in response to food in the intestines and stimulate secretion of enzymes from the pancreas and bile from the liver to aid in digestion. Bile and pancreatic enzymes break down carbohydrates, proteins, and lipids into smaller molecules that can be absorbed into the bloodstream.