(i) The cells of liver secrete bile juice, which helps in emulsification of fats. It also makes the acidic food coming from the stomach alkaline thus, facilitating action of pancreatic enzymes.
(ii) Gall bladder stores and concentrates the bile juice produced by the liver.
(iii) The villi increses the intestinal absorptive surface area. This ensures that there is more space for the food and its components to be absorbed.