Presentation on theme: "Digestive System Structures 2.07"— Presentation transcript:
1 Digestive System Structures 2.07 AKA:Alimentary CanalDigestive TractGastrointestinal TractUpper GILower GIApproximately 30’ in length from mouth to anus2.07 Remember the structures of thedigestive system
2 Functions of the Digestive System Physical breakdown of food.Chemical digestion of food into the end products of fat, carbohydrates, and protein.Absorb nutrients into blood capillaries of the small intestines.Eliminate waste products of digestion.
3 DefinitionsDigestion- the process of changing complex solid foods into simpler soluble forms which can be absorbed by body cellsEnzymes- chemical substances that promote chemical reactions in living things
4 Digestion Terminology Bolus:soft, pliable ballcreated from chewing and addition of saliva-slides down esophagus.Peristalsis:wavelike motions, moves food along esophagus, stomachand intestines.
5 DefinitionsFeces:undigested semi-solid consisting of bacteria, waste products, mucous andCelluloseDefecation:large intestine fills, defecation reflex triggered-colon and rectal muscles contract while internal sphincter relaxesexternal anal sphincter under conscious control
6 Digestive System Structures Primary structuresMouthEsophagusStomachSmall intestinesLarge intestinesAccessory structuresTongueTeethSalivary glandsPancreasLiverGall bladder2.07 Remember the structures of thedigestive system
7 In the mouth… Saliva softens food to make it easier to swallow Ptyalin in saliva converts starches into simple sugarUnder nervous control- just thinking of food can cause your mouth to water.
8 Structure of Organs of Digestion MouthFood enters digestive system through mouth (buccal cavity)covered with mucous membraneRoof of mouth is HARD PALATE (bone) and soft palateUVULA- flap that hangs off soft palate-prevents food from going up the nose when you swallow.
9 2.07 Remember the structures of the Buccal cavityTongueTeethSalivary GlandsPalateUvula2.07 Remember the structures of thedigestive system
10 Tongue Attached to floor of mouth Helps in chewing and swallowing Made of skeletal muscle attached to four bonesPapillae (taste buds) on the surface
11 2.07 Remember the structures of the TongueTaste buds on the surfaceSweetSourBitterSalty2.07 Remember the structures of thedigestive system
12 Salivary Glands Three pairs of glands Parotid glandSubmandibular glandSublingual glandPAROTID – largest salivary glands, become inflamed during mumpsSecrete saliva
13 Teeth Gingiva – gums, support and protect teeth Mastication – chewing, teeth helps in mechanical digestionDeciduous teeth- baby teeth (#20)Adult mouth has 32 teeth (Permanent).Did you know???Canine teeth are alsoknown as cuspids andeye teeth.
14 2.07 Remember the structures of the PalateHardSoftUvulaFlap of skinhanging in theback of the throat2.07 Remember the structures of thedigestive system
15 2.07 Remember the structures of the Pharynx (throat)NasopharynxOropharynxHypopharynx2.07 Remember the structures of thedigestive system
16 Esophagus Muscular tube 10” long Connects pharynx and stomach Esophageal wall layersMucosaSubmucosaMuscularExternal serous
17 In the Stomach… Gastric (digestive) juices are released Stomach walls churn and mix (This mixture is chyme)Small amount of chyme enters duodenum at a time controlled by pyloric sphincterTakes 2-4 hours for stomach to empty.When will Meagan’s stomach be empty if she last ate at 9a.m.?
18 Stomach Upper left quadrant of the of the abdominal cavity FundusBodyPylorusStomach has muscular coat that allows it to contract (peristalsis) and push food into the small intestine
19 2.07 Remember the structures of the StomachCARDIAC SPHINCTER-circular layer of muscle, controls passage of food into stomachPYLORIC SPHINCTER- valve, regulates the entrance of food into duodenumRUGAE- mucous coat lining of stomach in folds when the stomach is empty2.07 Remember the structures of thedigestive system
20 Small Intestines Where digestion is completed and absorption occurs Addition of enzymes from the pancreas and bile from liver/gallbladder
21 Small IntestinesDUODENUM- first segment, curves around pancreas, 12” longJEJUNUM- Second segment , 8 ft. longILEUM- Third segment, ft longABSORPTION- in small intestine, digested food passes into bloodstream and on to body cells, indigestible passes on to large intestine
22 2.07 Remember the structures of the Acessory organsPancreasSecretes digestive enzymesLocated behind stomachLiverNext slideGall BladderStores and concentrates bile until needed by body2.07 Remember the structures of thedigestive system
23 Liver Largest organ in the body Located below the diaphragm, upper right quadrantManufactures bileConnected to gallbladder and small intestine by ductsFunctions: produce and store glucose in the form of GYCOGEN-Detoxify alcohol, drugs and other harmful substancesManufacture blood proteinsPrepare urea from the breakdown of amino acidsStore Vitamins A, D, and B complex
24 Gallbladder Small green muscular sac secretes bile located inferior surface of the liverStores and concentrates bile until needed by body.When fatty foods digested, bile released by gallbladder.
25 In the Large intestine… Regulation of H2O balance by absorbing large quantities back into bloodstreamabsorbs Vitamin B complex and KBacterial action on digested food-decomposed products excreted through colon-bacteria form moderate amounts of B complex and Vitamin KGas formation 1-3 pints/day, pass it through the rectum (flatulence) 14 times a day, bacteria produce gas
26 Large Intestine Chyme - semi-liquid food Approx 2” in diameter 5’ Long AKA: colonCecum-lower right portion of large intestineAppendix: blind sac attached to the cecum, no known function, finger like projectionRectum- last portion of large intestineAnus- external opening
27 Sigmoid colonS shaped part of colon, which extends 7 to 8 inches as the rectum