1. Principles of Health Science
Digestive System
Principles of Health Science
Day 1

2. Thought for the Day & Warm-up
What is digestion? What is the function of your…
mouth?
stomach?
small intestine?
colon?

3. Agenda Objectives: Students will be able to… Lesson: Digestive System
describe the various organs in the digestive system and analyze their functions.
Lesson: Digestive System
Quiz 6: Monday, May 5th, 2014

4. Digestive System What is Digestion?
Physical and chemical breakdown of food for use by the body
The Digestive System consists of the alimentary canal and the accessory organs

5. Utilization of Nutrients
Mechanical Digestion
Mouth
Chemical Digestion
Stomach
Absorption
Small Intestine
Metabolism
Cells
Digestion – the process by which the body breaks down food into smaller parts, changes the food chemically, and moves the food through the digestive system.
Mechanical Digestion – food is broken down by the teeth in the oral cavity
Chemical Digestion – food is broken down by digestive enzymes secreted by the mouth, stomach, small intestines, and pancreas; most digestion occurs in the stomach
Absorption- The process by which blood picks up the digested nutrients. The nutrients are then carried by the circulatory system to every cell in the body. Most absorption of nutrients occurs in the small intestine
Metabolism-The process in which nutrients are used by the cells. Nutrients are combined with oxygen and energy and heat are released.

6. Alimentary Canal
Long muscular tube that begins at the mouth and ends at the anus
Accessory organs:
Salivary glands, teeth, liver, gallbladder, pancreas

7. Mouth Receives food as it enters the body Teeth Tongue
Food is tasted, broken down by teeth, lubricated by saliva, & swallowed
Teeth
Mastication
Tongue
Taste/manipulate food
Hard/Soft Palate
Separates the mouth from the nasal cavities & nasopharynx
Uvula
Prevents food from entering the nasopharynx
Salivary glands
Produce saliva

8. Pharynx (Throat) Carrier for both air and food Food Bolus
Carries food to the esophagus
Food Bolus
When food is mixed saliva
When bolus swallowed, epiglottis closes to prevent food from entering the trachea

9. Esophagus
Muscular tube behind the trachea that carries food to the stomach
Peristalsis moves food toward stomach
Rhythmic, wave-like muscle movement

10. Stomach Digests/breaks down food with gastric juices (acids)
Two circular muscles that keep food in the stomach
Cardiac sphincter
Between the esophagus/stomach
Pyloric sphincter
Between the stomach/small intestine
Food stays in the stomach 1–4 hours
Chyme
semi-liquid material of digested food

11. Small Intestine Absorbs nutrients into the bloodstream through villi
Fingerlike projections on the lining of the intestines
Small intestine
i. Duodenum
Connects to the stomach & receives bile and pancreatic juices
ii. Jejunum
Middle section
ii. Ileum
Connects to the large intestine
(continues)

12. Large Intestine
Absorbs water and stores indigestible materials (feces)
Cecum
Appendix
Colon
Ascending
Transverse
Descending
Sigmoid
Rectum
Storage area for feces
Anus
Expels fecal material/stool
Constipation- when the large intestine absorbs too much water, and stools are hard and difficult to pass
Diarrhea- when the large intestine does not absorb enough water, and the stools are watery/liquid

13. Liver & Gallbladder Liver Gallbladder Bile Secretes bile
Detoxifies substances (alcohol)
Gallbladder
Stores bile until it is ready to be released into the small intestine
Bile
Helps to digest/break up fats

14. Pancreas Fish-shaped organ located behind the stomach Produces
pancreatic juices to digest food (small intestine)
insulin to metabolize sugars (bloodstream)

15. Diagram Labeling Word Bank
Esophagus Stomach Small Intestine Cecum Ascending Colon Transverse Colon
Descending Colon
Sigmoid Colon
Rectum
Anus
Liver
Gallbladder

16. Diagram Answers A. Liver B. Gallbladder C. Ascending Colon
D. Small Intestine
E. Cecum
F. Rectum
G. Anus
H. Sigmoid Colon
I. Descending Colon
J. Transverse Colon
K. Stomach
L. Esophagus

17. Labeling

18. Activity: Include the main structures from #5-12
Create a children’s book about where poop comes from.
Include the main structures from #5-12
Write at least 1 FACT from your notes about each structure
Include what happens with
Constipation
Diarrhea
This is due TODAY at the END of CLASS!

19. Review & Looking Ahead…
Discussed: the various organs in the digestive system and analyze their functions.
Next class topic: Wellness - Nutrition
Quiz 6: Monday, May 5th, 2014