It is divisible into duodenum and ileum. Pancreatic juice is secreted from the pancreas and bile through the gallbladder from the liver to the small intestine, which helps in completion of digestion. Absorption of the digested nutrients in digestive system of a frog occurs in small intestine.Absorption unabsorbed nutrients and reabsorption of water takes place in the large intestine. Liquid wastes are in frog is passed to the urinary bladder, while solids are routed to the cloaca.he digestive system of frog consists of digestive tract and the accessory organs which help to process the food consumed into small molecules (nutrients) which then can be easily absorbed and then utilized by the cells of the body.