Presentation on theme: "The Digestive System: Anatomy"— Presentation transcript:
1 The Digestive System: Anatomy Digestion: breakdown of foods and the absorption of nutrientsAlimentary canal includes:MouthPharynxEsophagusStomachSmall intestineLarge intestineRectumAnus
2 The Digestive System: Anatomy Walls of alimentary canal consists of:Mucosa (carries out secretion and absorption)Submucosa (carries away absorbed materials)Muscular layer (provides movement of tube)Serosa (protects underlying tissues)
3 The Digestive System: Anatomy Accessory organs of alimentary canal include:TeethTongueSalivary glandsLiverGallbladderPancreas
4 The AbdomenRight upper quadrant (RUQ): liver, gallbladder, some of colon and small intestineLeft upper quadrant (LUQ): stomach, spleen, some of colon and small intestineRight lower quadrant (RLQ): cecum, ascending colon, appendixLeft lower quadrant (LLQ): descending and sigmoid parts of colon
6 Mouth Consists of lips, cheeks, gums, teeth, tongue Lined by a mucous membraneRoof is formed by hard and soft palatesSalivary glands produce nearly 1.5 L of saliva daily.Saliva serves as a binder for chewed food and as a mouth lubricant.
7 OropharynxTubular structure extending vertically from back of mouth to esophagus and tracheaAutomatic movement of pharynx during swallowingMoves liquids and solids into esophagus and away from trachea
8 Esophagus Collapsible tube about 10″ long Extends from end of pharynx to stomachContractions of muscles in the esophagus wall propel food to the stomach.Liquids pass with little assistance.
9 Stomach Hollow organ in left upper quadrant Converts food to mixed, semisolid mass (chyme)Moves chyme into small bowel in regular, small amounts
10 Pancreas Two intertwined portions: Exocrine pancreas secretes pancreatic juiceEndocrine pancreas (islets of Langerhans) produces insulinInsulin regulates the amount of glucose in blood.
11 Liver Largest solid organ in abdomen Renders poisonous substances produced by digestion harmlessForms factors necessary for blood clotting, plasma production, immune responseProduces bile to help digest fatStores sugar or starch for immediate use
12 Small Intestine Major hollow organ of abdomen Absorbs more than 90% of products of digestionInto veins to transport to liverComponents include:DuodenumJejunumIleum
13 Large Intestine Components include: CecumColonRectumAbsorbs final 5% to 10% of digested food and waterForms solid stool to pass out of body through anus
14 Appendix3″ to 4″ longOpens into cecum (first part of large intestine)Easily becomes infected, producing appendicitisOne of major causes of severe abdominal distress
15 Rectum Lowermost end of colon Large, hollow organ Stores quantities of feces until expelledAnus is 2″ canal at end, lined with skin.Sphincters (circular muscles) control the escape of liquids, gases, and solids.Voluntarily and automatically
16 The Digestive System: Physiology Functions of the digestive system:IngestionMechanical processingDigestionSecretionAbsorptionExcretion
17 The Digestive System: Physiology In succession, different secretions (primarily enzymes) are added to food by:Salivary glandsStomachLiverPancreasSmall intestine
18 The Digestive System: Physiology Converts food into basic sugars, fatty acids, amino acidsThese products cross wall of intestine and travel through portal vein to liverLiver further processes and stores or transports to heartCirculatory system then nourishes all cells