1 / 40

The Digestive System

The Digestive System. Introduction- FUNCTION. Preparing food for absorption and use by body cells. arteri/o- artery bio- life cheil/o- lips clysis- washing or irrigation col/o- large intestine ecstasia- dilation or stretching gingiv/o- gums hem/o- blood hemat/o- blood

casey-hopkins
Download Presentation

The Digestive System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Digestive System

  2. Introduction-FUNCTION • Preparing food for absorption and use by body cells

  3. arteri/o- artery bio- life cheil/o- lips clysis- washing or irrigation col/o- large intestine ecstasia- dilation or stretching gingiv/o- gums hem/o- blood hemat/o- blood lys- destruct myc/o- fungus o- egg Orrhagia – hemorrhage orrhaphy- suture, stitch pancreat/o- pancreas proct- rectum and anus rect/o- rectum scop/o- examine spermat/o- sperm ur/o- urine ureter/o- ureter urethr/o- urethra Vocab 17Quiz on Friday 3/28

  4. Introduction-DIVISIONS 1. Alimentary canal aka gastrointestinal tract (GI)- approx. 9 m long • Digests food • Absorbs digested food through lining • Mouth, pharynx, esophagus, stomach, small intestine, large intestine

  5. Introduction-DIVISIONS 2. Accessory digestive organs • Teeth • tongue, • gall bladder • salivary glands • Liver • pancreas

  6. Introduction-DIGESTIVE PROCESSES • 1. ingestion • 2. propulsion via swallowing and peristalsis • 3. mechanical digestion e.g. mastication, stomach churning

  7. Introduction-DIGESTIVE PROCESSES 4. chemical digestion via enzymes –ase Examples: lipase, amylase, proteases like pepsin and trypsin Very specific in action Function at a specific pH 5. absorption 6. defecation

  8. Introduction-4 tissue layers of GI 1. mucosa- innermost; epithelial; secretion of dig juices; absorption; protection against infection 2. submucosa- connective; vascular 3. muscularis- smooth muscle; mixes and propels food; sphincters 4. serosa- outermost;areolar + squam.

  9. Mouth • Aka oral cavity or buccal cavity • Functions- • Ingestion • Propulsion • mechanical digestion • chemical digestion • deglutition (swallowing)

  10. Mouth-LIPS Aka labia; skeletal m. covered by skin 1. actually extends from inferior nose to superior chin. The reddened part is the red margin. Philtrum- shallow vertical groove of upper lip Labial frenulum- median fold that joins each lip to the gum

  11. Mouth- CHEEKS • Mostly buccinator muscle and fat

  12. Mouth-PALATE Roof of mouth 1. hard palate- underlain by bone; midline ridge is the raphe 2. soft palate- mostly sk. Muscle fingerlike uvula  closes of nasopharynx when swallowing

  13. Mouth-TONGUE 1. mostly skeletal muscle 2. mixes food with saliva to form bolus 3. Lingual frenulum secures tongue to mouth 4. Root, tip, body

  14. Mouth-TONGUE 5. papillae- projections Vallate- v-shaped; at back of tongue; taste buds Fungiform- taste buds; mushroom-shaped Filiform- roughness to tongue; conical- shaped

  15. Mouth-SALIVARY GLANDS 1. functions of saliva Cleans mouth Dissolves food so it can be tasted Moistens food and aids in compacting it into a bolus Contains enzymes (amylase) to break down starches

  16. Mouth-SALIVARY GLANDS 2. types • Parotid glands • Submandibular glands • Sublingual glands

  17. MOUTH-Teeth 1. Allow for mastication (chewing) 2. typical tooth Crown- exposed portion Neck- surrounded by gingivae (gums) Root- fits into sockets (alveoli)

  18. MOUTH-Teeth 3. deciduous teeth aka milk or baby teeth; approx 20 4. permanent teeth- 32 5. dental formula for perm. Teeth: 2I, 1C, 2 PM, 3M x 2 = 32 teeth 2I, 1C, 2 PM, 3M

  19. Esophagus 25 cm A. with cardiac or gastroesophageal sphincter B.Peristalsis- wave-like ripple in hollow organs

  20. Stomach A. Size varies because of distension- holds 1-1.5 L B. Divisions 1. Cardiac region- eso dumps into stomach 2. Fundus- enlarged part to L & above opening of the eso to the stomach 3. Body- central 4. Pylorus- lower portion 5. Greater (lateral) & lesser (medial) curvatures with greater & lesser omenta

  21. Stomach C. Sphincters 1. Cardiac- eso into stomach 2. Pyloric- stomach into duodenum of small intestine

  22. Talk about hard to swallow!!!

  23. Stomach D. Functions 1. Food storage 2. secretes gastric juice- pepsin 3. churns the food (mechanical) 4. chemical digestion of proteins by pepsin 5. limited absorption 6. destroys pathogenic bacteria 7. propulsion of food into small intestine

  24. Stomach: A closer look

  25. Small Intestine A. Divisions 1. duodenum- uppermost; 25 cm 2. jejunum- middle; 2.5 m 3. ileum- end; 3.5 m

  26. Small Intestine B. Intestinal lining with plicae (folds) that contain villi. Villi increase surface area which allows for more absorption. C. Functions 1. mechanical digestion 2. propulsion 3. chemical digestion 4. absorption

  27. Large Intestine A. Divisions 1. Cecum Small (5-8 cm) “blind pouch” With vermiform appendix (“worm-shape”) appendix- immunity? Intestinal flora?

  28. Large Intestine A. Divisions 2. Colon Ascending- vertical; with ileocecal valve Transverse- horizontal; above sm int Descending- vertical Sigmoid- s-shaped curve

  29. Large Intestine B. Functions 1. chemical digestion 2. absorption of remaining water via osmosis 3. propulsion 4. defecation

  30. Accessory Digestive Organs A. Liver- largest gland in the body 1. Lobes Right- R lobe proper, caudate lobe, quadrate lobe Left

  31. Accessory Digestive Organs A. Liver- largest gland in the body 2. Functions • detoxify substances • Secrete bile that will eventually go into the duodenum to break up fat • Metabolism of proteins, fats, carbs • Store substances like Fe, vit A, vit D • Hematopoeisis in fetus

  32. Accessory Digestive Organs B. Gall Bladder 1. green sac about the size of a kiwi 2. stores 30-50 ml of bile

  33. Accessory Digestive Organs C. Pancreas 1. resembles fish with head and neck in the C-shaped curve of the duodenum 2. Functions Secrete pancreatic juice with digestive enzymes like trypsin Secrete insulin hormone that affects carb metabolism Secrete glucagon

More Related