1. PowerPoint Lecture Outlines to accompany
Hole’s Human
Anatomy and Physiology
Tenth Edition
Shier w Butler w Lewis
Chapter 17
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
17-1

2. DIGESTIVE SYSTEM QUIZ 1
What are the 6 functions of the digestive system?

3. Which one refers to eating?
Which one refers to releasing waste materials from the body?
Which one refers to the movement of food through the alimentary canal?
Which one refers to food molecules being broken down into smaller molecules?
Which one refers to food molecules that are broken down and crossing into the blood stream?
Which one refers to the process of chewing?

4. Chapter 17 Digestive System
Functions of Digestive System
ingestion
mechanical digestion
chemical digestion
propulsion
absorption
defecation
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5. Major Organs
17-3

6. Alimentary Canal
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7. Alimentary Canal Wall
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8. Movements of the Tube
mixing movements
peristalsis
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9. Innervation of the Tube
submucosal plexus – controls secretions
myenteric plexus – controls gastrointestinal motility
parasympathetic impulses – increase activities of digestive system
sympathetic impulses – inhibit certain digestive actions
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10. Mouth ingestion mechanical digestion
prepares food for chemical digestion
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11. Tongue
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12. Palate
roof of oral cavity
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13. Primary Teeth
8 incisors
4 cuspids
8 molars
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14. Secondary Teeth
17-12

15. Section of a Tooth
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16. Salivary Glands
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17. Secretions of Salivary Glands
Parotid glands
clear
water, serous fluid
rich in amylase
Sublingual glands
primarily mucus
most viscous
Submandibular glands
primarily serous fluid
some mucus
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18. Pharynx
17-16

19. Swallowing Mechanism soft palate and uvula raise
hyoid bone and larynx elevate
epiglottis closes off top of trachea
longitudinal muscles of pharynx contract
inferior constrictor muscles relax and esophagus opens
peristaltic waves push food through pharynx
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20. Swallowing Mechanism
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21. Esophagus
17-19

22. Stomach
17-20

23. Radiograph of Stomach
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24. Lining of Stomach
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25. Gastric Secretions pepsinogen from chief cells inactive form of pepsin
mucus
from goblet cells and mucous glands
protective to stomach wall
pepsin
from pepsinogen in presence of HCl
protein splitting enzyme
intrinsic factor
from parietal cells
required for vitamin B12 absorption
hydrochloric acid
from parietal cells
needed to convert pepsinogen to pepsin
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26. Phases of Gastric Secretion
Cephalic phase
triggered by smell, taste, sight, or thought of food
parasympathetic impulses trigger gastric juice secretion
Gastric phase
triggered by presence of food in stomach
gastrin released
gastric juice secreted
Intestinal phase
triggered by movement of food into small intestine
intestinal cells release intestinal gastrin
secretion of gastric juice
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27. Regulation of Gastric Secretions
17-25

28. Gastric Absorption some water certain salts
certain lipid-soluble drugs
alcohol
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29. Mixing and Emptying Actions
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30. Enterogastric Reflex
regulates the rate at which chyme leaves the stomach
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31. Pancreas
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32. Pancreatic Juice
pancreatic amylase – splits glycogen into disaccharides
pancreatic lipase – breaks down triglycerides
trypsin, chymotrypsin, and carboxypeptidase – digest proteins
nucleases – digest nucleic acids
bicarbonate ions – make pancreatic juice alkaline
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33. Regulation of Pancreatic Secretions
acidic chyme stimulates release of secretin
secretin stimulate release of pancreatic juice
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34. Liver
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35. Hepatic Lobule
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36. The Paths of Blood and Bile in Hepatic Lobule
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37. Liver Functions produces glycogen from glucose
breaks down glycogen into glucose
converts noncarbohydrates to glucose
oxidizes fatty acids
synthesizes lipoproteins, phospholipids, and cholesterol
converts carbohydrates and proteins into fats
deaminates amino acids
forms urea
synthesizes plasma proteins
converts some amino acids to other amino acids
stores glycogen, vitamins A,D, B12, iron, and blood
phagocytosis of worn out RBCs and foreign substances
removes toxins from blood
produces and secretes
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38. Composition of Bile water bile salts bile pigments cholesterol
emulsification of fats
absorption of fatty acids, cholesterol, and fat-soluble vitamins
bile pigments
cholesterol
electrolytes
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39. Gallbladder
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40. Regulation of Bile Release
fatty chyme entering duodenum stimulate gallbladder to release bile
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41. Three Parts of Small Intestine
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42. Mesentery
suspends portions of the small intestine from the posterior abdominal wall
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43. Intestinal Villus
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44. Intestinal Epithelium
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45. Wall of Small Intestine
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46. Secretions of Small Intestine
peptidase – breaks down peptides into amino acids
sucrase, maltase, lactase – break down disaccharides into monosaccharides
lipase – breaks down fats into fatty acids and glycerol
enterokinase – converts trypsinogen to trypsin
somatostatin – hormone that inhibits acid secretion by stomach
cholecystokinin – hormone that inhibits gastric glands, stimulates pancreas to release enzymes in pancreatic juice, stimulates gallbladder to release bile
secretin – stimulates pancreas to release bicarbonate ions in pancreatic juice
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47. Regulation of Small Intestinal Secretions
mucus secretion stimulated by presence of chyme in small intestine
distension of intestinal wall activates nerve plexuses in wall of small intestine
parasympathetics trigger release of intestinal enzymes
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48. Absorption in the Small Intestine
monosaccharides and amino acids
through facilitated diffusion and active transport
absorbed into blood
electrolytes and water
through diffusion, osmosis, and active transport
absorbed into blood
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49. Absorption in the Small Intestine
fatty acids and glycerol
several steps
absorbed into lymph and blood
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50. Movements of the Small Intestine
mixing movements
peristalsis – pushing movements
segmentation – ringlike contractions
overdistended wall triggers peristaltic rush resulting in diarrhea
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51. Large Intestine
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52. Large Intestinal Wall
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53. Functions of Large Intestine
little or no digestive function
absorbs water and electrolytes
secretes mucus
houses intestinal flora
forms feces
carries out defecation
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54. Movements of Large Intestine
slower and less frequent than those of small intestine
mixing movements
peristalsis
mass movements usually follow meals
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55. Feces water electrolytes mucus bacteria
bile pigments altered by bacteria provide color
smell produced by bacterial compounds
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56. Life-Span Changes teeth become sensitive gums recede
teeth may loosen or fall out
heartburn more frequent
constipation more frequent
nutrient absorption decreases
accessory organs age but the effects are less noticeable
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57. Clinical Application Hepatitis inflammation of the liver
most commonly caused by viral infection
can be caused by reactions to drug, alcoholism or autoimmunity
Signs and Symptoms
headache
low fever
fatigue
vomiting
rash
foamy urine
pale feces
jaundice
pain
Hepatitis A – not washing hands or eating raw shellfish
Hepatitis B – chronic; serum
Hepatitis C – serum
Hepatitis D – very severe; only produces symptoms if infected with B; serum
Hepatitis E, F, G – more rare
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