1. Anatomy and Physiology of the Digestive System
Chapter 13: The Digestive System and Nutrition
Lesson 13.2
Anatomy and Physiology of the Digestive System

2. Activities of Digestion
(1) ingestion
getting food into the body
(2) propulsion - Peristalsis
moving food along GI tract
(3) mechanical breakdown
breaks food into smaller pieces- chew your food!
increases surface area of food-increases efficiency

3. Activities of Digestion
(4) chemical breakdown
also known as digestion – this is the definition of digestion
enzymes –make digestion faster (amylase, pepsinogen, protease, lipase, etc…)
(5) absorption
digested food particles moved into blood
(6) defecation -poop

4. Activities of Digestion

5. Layers of the Alimentary Canal
mucosa
innermost layer
adjacent to lumen- epithelial tissue- absorption
Submucosa –lots of blood vessels
below mucosa

6. Layers of the Alimentary Canal
muscularis externa – causes peristalsis
circular muscle
longitudinal muscle
serosa – connective tissue- keeps shape & protects
outermost layer
peritoneum
visceral
parietal
LUMEN
submucosa
mucosa

7. Layers of the Alimentary Canal

8. Review and Assessment True or False?
1. Mechanical breakdown decreases the surface area of food.
2. The mucosa is adjacent to the lumen.
3. Peritoneum is serosa.
4. In absorption, digested food moves into the blood.

9. Digestive Organs and Their Functions

10. The Oral Cavity Lips- keep food in Tongue – moves food to teeth
Cheeks-keep food in
palate
Hard-separate nasal from oral cavities
Soft-moves to accommodate swallowing

11. The Nasal Cavity passageway for air uvula hangs from soft palate
keeps food out of nasal cavity when swallowing

12. Teeth and Gums
Gum- protect tooth roots and steady teeth in jaw bones – teeth constantly move
gingiva
teeth
Deciduous- baby teeth (lose them)
permanent
Incisor-slicing
Canine-tearing
Molar-grinding

13. Anatomy of the Tooth

14. Salivary Glands parotid submandibular Sublingual saliva
Together provide saliva based on need.
saliva
water
enzymes –break down food (amylase)

15. Pharynx Nasopharynx-air Oropharynx-directs food to esophagus
Laryngopharynx-splits resp. & dig. systems
glottis
Epiglottis-Heimlich maneuver

16. Esophagus connects pharynx to stomach peristalsis
muscle contraction changes size of tube
food is moved through GI tract

17. Stomach regions three layers of muscle
cardia
fundus
body
pyloric region
three layers of muscle
-all of this helps the stomach churn

18. Lining of the Stomach gastric gland mucus-secreting cells
parietal cells-secrete HCl
chief cells-secrete pepsinogen (& renin)
enteroendocrine cells-secrete peptide hormones (full feeling)

19. Chemical Reactions in the Stomach
protein-digesting enzymes (pepsinogen)
chyme formation- bolus- allows smoother travel through intestines
stomach contractions

20. Review and Assessment
Match these words with 1–4 below: canine, fundus, parotid, esophagus.
1. region of stomach
2. connects pharynx to stomach
3. a type of tooth
4. a type of salivary gland

21. Small Intestine segments lining
Duodenum- connection to stomach. Place of bile and pancreatic juice introduction
Jejunum – absorption
Ileum- connection to the colon via cecum
lining
Villi – finger-like (also known as microvilli) increase surface area
intestinal crypts- produce mucus and secretions to move chyme along the alimentary canal

22. Small Intestine chemical breakdown absorption into the blood
emulsification by bile
break down by enzymes
absorption into the blood
from capillaries to the blood
lacteal to lymph
vitamin B12

23. The Liver functions of the liver- bile production
maintains nutrients in blood
converts one nutrient to another
stores nutrients
inactivates toxins
hepatic portal vein- cleansed blood back to the circ. system
parts of the liver
Lobules- divisions
Hepatocytes-cells
blood vessels
bile canaliculi- direct bile to ducts
bile salts

24. Liver and Gallbladder

25. The Gallbladder functions of the gallbladder
stores bile produced by liver
releases bile when fat-containing chyme is in duodenum

26. Pancreas pancreatic juices- exocrine glucose regulation- endocrine
contain digestive enzymes
glucose regulation- endocrine
beta cells–insulin
alpha cells–glucagon

27. Large Intestine regions
Cecum- “garbage dump” first place to receive spent chyme
colon
Ascending
transverse
descending
sigmoid
All used to reabsorb water

28. Rectum, Anal Canal, and Anus
sphincters
internal
external
Fecal material storage
For control

29. Review and Assessment
Match these words with 1–4 below: jejunum, sigmoid, beta cells, gallbladder. 1. a region of the colon 2. a region of the small intestine 3. stores bile 4. produce insulin