The accessory digestive glands include the salivary glands, the liver and the pancreas.
(i) Humans have three pairs of salivary glands, i.e., the parotids, submandibulars and sublinguals. They secrete major amount (about 1L) of the saliva, each day. The parotids are the largest glands in the cheek region near the ears. The submandibular glands are located towards the posterior end of the lower jaw. Sublingual glands are the smallest, present at the anterior part of the floor of the mouth.
(ii) The liver is the largest gland in the body. It weighs about 1.5 kg, lies immediately under the diaphragm. The gall bladder is a small and elongated muscular sac situated below die liver.
(iii) The pancreas is an elongated gland, that is situated near the junction of the stomach and the duodenum. Both the liver and pancreas act as glands whereas, the gall bladder acts as a storing organ.