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The digestive system is responsible for breaking down food, absorbing nutrients from the food, and ridding the body of waste products from the food. It is roughly nine meters long and begins at the mouth and ends at the anus.
Kids have 20 teeth, but by the time they are fully grown, they should have 32 teeth (some people do have less!).
The esophagus is the second step to digestion and closely follows the oral cavity – once swallowing has initiated.
The digestive system consists of the: the alimentary tract mouth, pharynx , esophagus, stomach, small and large intestines, rectum and anus the accessory organs salivary glands, liver, gall bladder and pancreas
The stomach is divided into the fundic, cardiac, body, and pyloric regions. The stomach has three layers of muscle: an outer longitudinal layer, a middle circular layer, and an inner oblique layer. The inner lining consists of four layers: the serosa, the muscularis, the submucosa, and the mucosa. The mucosa is densely packed with gastric glands, which contain cells that produce digestive enzymes, hydrochloric acid, and mucus. The stomach is a multi-functional organ, it stores food, breaks it down and then empties it into the small intestineh, or oral cavity, is the first part of the digestive tract. It is adapted to receive food by ingestion, break it into small particles by mastication, and mix it with saliva. The lips, cheeks, and palate form the boundaries. The oral cavity contains the teeth and tongue and receives the secretions from the salivary glands.
The small intestine consists of three sections. duodenum, jejunum and ileum which attaches to the first portion of the large intestine.
Function digestion, and absorption . The small intestine finishes the process of digestion, absorbs the nutrients, and passes the residue on to the large intestine.
The liver, gallbladder, and pancreas are accessory organs of the digestive system that are closely associated with the small intestine.
The large intestine is made up of three portions: the ascending, transverse and descending colon. It is the portion of the digestive system most responsible for absorption of water from the indigestible residue of food. The ileocecal valve of the ileum (small intestine) passes material into the large intestine at the cecum. Material passes through the ascending, transverse, descending and sigmoid portions of the colon, and finally into the rectum. From the rectum and anus, the waste is expelled from the body.