Digestive system of gastropods jaw structure can be ribbed or smooth: Some species have no jaw. Salivary glands plays primary role in the anatomical and physiological adaptations of the digestive system of predatory gastropods. Ducts from large salivary glands lead into the buccal cavity, and the oesophagus also supplies the digestive enzymes that help to break down the food. Salivary secretions lubricate the food and they also contain bioactive compounds. The mouth of gastropods opens into an oesophagus, which connects to the stomach. Because of torsion, the oesophagus usually passes around the stomach, and opens into its posterior portion, furthest from the mouth. In
Digestive system of humpback whales digest the chitin in the exoskeletons of krill and prey swallowed whole. The duodenal ampulla can be described as the atrium of the small intestine and is a dilated sac forming the beginning of the duodenum. The duodenum prepares many nutrients from the digested matter (chyme), for absorption, which takes place in the intestines, and is the principal site for iron absorption. Digestive system of humpback whales The digestive system of humpback whales ("Megaptera novaeangliae") is adapted to digest tiny crustaceans such as krill, plankton, and small fish (including herring and mackerel) which the whale filters from the ocean using