The Digestive System of a Human
The process starts at the mouth. Your teeth grind food as it is mixed with saliva, produced from the salivary glands in the mouth. An enzyme in the saliva begins the digestive process by breaking the food. After chewing the food, your tongue rolls and pushes the food past the pharynx and down the esophagus. There waves of muscle contractions, know as peristalsis, carry the food to the stomach. Gravity also plays a role, but it is not essential. Newt comes the stomach. Some substances are absorbed directly through the stomach wall. Most food however must undergo further digestion. Contractions of the muscular stomach wall produce a churning motion that mixes the food with strong chemicals produced in special glands in the stomach lining. Once the food is turned into chyme it is squirted down into the small intestine. Here muscular contractions move the chyme along as a number of digestive chemicals work on it. The pancreas contributes a salt, sodium bicarbonate, that neutralizes the acid from the stomach. This creates the best conditions for the work of the digestive enzymes. Glands in the walls of the intestines also produce digestive enzymes. These enzymes break down the food molecules and the nutrients are absorbed into the blood stream. After the small intestine the chyme goes into the large intestine. By the time the chyme reaches the large intestine it is basically completely digested. The main job of the large intestine is to remove water from the undigested food matter and form this matter into solid masses. These are called feces which are eliminated from the body through the anus.
The process starts at the mouth. Your teeth grind food as it is mixed with saliva, produced from the salivary glands in the mouth. An enzyme in the saliva begins the digestive process by breaking the food. After chewing the food, your tongue rolls and pushes the food past the pharynx and down the esophagus. There waves of muscle contractions, know as peristalsis, carry the food to the stomach. Gravity also plays a role, but it is not essential. Newt comes the stomach. Some substances are absorbed directly through the stomach wall. Most food however must undergo further digestion. Contractions of the muscular stomach wall produce a churning motion that mixes the food with strong chemicals produced in special glands in the stomach lining. Once the food is turned into chyme it is squirted down into the small intestine. Here muscular contractions move the chyme along as a number of digestive chemicals work on it. The pancreas contributes a salt, sodium bicarbonate, that neutralizes the acid from the stomach. This creates the best conditions for the work of the digestive enzymes. Glands in the walls of the intestines also produce digestive enzymes. These enzymes break down the food molecules and the nutrients are absorbed into the blood stream. After the small intestine the chyme goes into the large intestine. By the time the chyme reaches the large intestine it is basically completely digested. The main job of the large intestine is to remove water from the undigested food matter and form this matter into solid masses. These are called feces which are eliminated from the body through the anus.