Salivary gland: it secretes saliva which contains ptyalin, an enzyme that breaks starch (polysaccharide)into maltose (disaccharide).
Gastric gland: it secretes gastric juice which contains HCl (hydrochloric acid) which softens food, kills bacteria present in food due to acidic nature, stops the action of saliva, provides acidic environment for the enzymes present in gastric juice to act.,
Liver: it secretes bile which helps to: emulsifies fat, helps in fat absorption, provides alkaline medium Firstly to neutralize the acid from the stomach and secondly to activate the pancreatic juices to act on food.
Pancreas: it secretes pancreatic juice which contains trypsin, amylase, lipase. Trypsin helps in the breakdown of proteins, peptones, peptides into an amino acid. Amylase helps in the breakdown of starch into maltose. Lipase helps in the breakdown of fat into fatty acids and glycerol.
Intestinal glands: it secretes intestinal juice (succus entericus) which contains an enzyme that helps in the breakdown of carbohydrates, proteins, fats.