Digestive System http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Functions of the Digestive System Ingestion = Food enters the mouth. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Functions of the Digestive System Ingestion = Food enters the mouth. Digestion = Process that breaks food down into small molecules http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Functions of the Digestive System Ingestion = Food enters the mouth. Digestion = Process that breaks food down into small molecules Mechanical digestion = Food is chewed and churned. Chemical digestion = Breaks down large food molecules into smaller molecules to be absorbed by cells http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Functions of the Digestive System Ingestion = Food enters the mouth. Digestion = Process that breaks food down into small molecules Absorption = Small molecules of food are taken into the body cells. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Functions of the Digestive System Ingestion = Food enters the mouth. Digestion = Process that breaks food down into small molecules Absorption = Small molecules of food are taken into the body cells. Elimination = Wastes made of unabsorbed food molecules pass out of the body. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg Large Intestine

Organs of the Digestive Tract Mouth = Digestion starts here. http://commons.wikimedia.org/wiki/Mouth

Organs of the Digestive Tract Mouth = Digestion starts here. The tongue & teeth mechanically break food up. http://openclipart.org/detail/1040/open-mouth-by-johnny_automatic

Organs of the Digestive Tract Mouth = Digestion starts here. The tongue & teeth mechanically break food up. Saliva chemically digests food. Saliva = Mostly made of water, also contains mucus and enzymes http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Mouth = Digestion starts here. The tongue & teeth mechanically break food up. Saliva chemically digests food. Saliva = Mostly made of water, also contains mucus and ptyalin (an enzyme) When swallowing, the epiglottis (a small flap of tissue) automatically closes over the trachea (windpipe). http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Esophagus Smooth muscles force food into the mucus-lined esophagus. Rhythmic muscular contractions (peristalsis) push food downward. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Stomach Food undergoes mechanical digestion when stomach muscles churn the food. Chemical digestion happens when hydrochloric acid (HCl) and pepsin break down the complex proteins. Peristalsis pushes the food toward stomach’s exit. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Small Intestine (6 meters long) Most digestion happens here. Intestinal juice (full of enzymes) breaks down food. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Small Intestine (6 meters long) Most digestion happens here. Intestinal juice (full of enzymes) breaks down food. Digestive Helpers Liver = Bile is produced here (Bile breaks up fats like dish detergent breaks up grease.). http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Small Intestine (6 meters long) Most digestion happens here. Intestinal juice (full of enzymes) breaks down food. Digestive Helpers Liver = Bile is produced here (Bile breaks up fats like dish detergent breaks up grease.). Gall bladder = Bile is stored here until released into the small intestine. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Small Intestine (6 meters long) Most digestion happens here. Intestinal juice (full of enzymes) breaks down food. Digestive Helpers Liver = Bile is produced here (Bile breaks up fats like dish detergent breaks up grease.). Gall bladder = Bile is stored here until released into the small intestine. Pancreas = Produces pancreatic juices that are released into the small intestine to break down proteins, starches, and fats http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Small Intestine (6 meters long) Most digestion happens here. Intestinal juice (full of enzymes) breaks down food. Digestive Helpers Liver Gall bladder Pancreas Digested food is absorbed through the villi in the small intestine into a network of blood vessels that carry the nutrients to all parts of the body. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Small Intestine (6 meters long) Most digestion happens here. Intestinal juice (full of enzymes) breaks down food. Digestive Helpers Liver, Gall bladder, Pancreas Digested food is absorbed through the villi into a network of blood vessels that carry the nutrients to all parts of the body. e) By the time food leaves the small intestine, it is empty of all nutrients except water. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Large Intestine (1.5 meters long) Undigested food spends 18–24 hours here, and most of the water is absorbed. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Large Intestine (1.5 meters long) Undigested food spends 18–24 hours here, and most of the water is absorbed. Helpful bacteria living in the large intestine make vitamins K and B. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Large Intestine (1.5 meters long) Undigested food spends 18–24 hours here, and most of the water is absorbed. Helpful bacteria living in the large intestine make vitamins K and B. Materials not absorbed form into solid waste (dead bacteria, some fat and protein, undigested food, dried out parts of digestive juices, and old intestinal cells). http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg

Organs of the Digestive Tract Large Intestine (1.5 meters long) Undigested food spends 18–24 hours here, and most of the water is absorbed. Helpful bacteria living in the large intestine make vitamins K and B. Materials not absorbed form into solid waste (dead bacteria, some fat & protein, undigested food, dried out parts of digestive juices, and old intestinal cells). Solid waste passes into the rectum and is stored until it is eliminated from the body through the anus. http://commons.wikimedia.org/wiki/File:Digestive_system_simplified.svg