1. The Wonderful World of Digestion
Digestion Ingestion

2. Digestion Is A Factory
The function of the DIGESTIVE SYSTEM is to turn the food we eat into energy!!!

3. MECHANICAL DIGESTION CHEMICAL DIGESTION
Food is ground in the mouth by teeth
CHEMICAL DIGESTION
Saliva begins breaking down carbohydrates into simple sugars
Chemical Digestion
(saliva)
Mechanical Digestion
(teeth)

4. Stomach Food enters the stomach through the esophagus
HYDROCHLORIC ACID and PEPSIN begin breaking down the proteins.
Muscles in the stomach work to “grind” the food.
Esophagus
Stomach

5. Food enters the SMALL INTESTINE
Digestive enzymes from the liver and PANCREAS digest the fats.
Nutrients enter the blood through VILLI.
Enzymes from liver and pancreas
Small intestine
Nutrients absorbed into blood

6. Small intestine Nutrients reach every cell in the body from the blood.
Circulatory System
(blood vessels)

7. “Food” moves into the LARGE INTESTINE where some water, vitamins and minerals return to the blood. The solid waste is prepared to exit the body. Ci
rculatory
system
Descending colon
Large Intestine
(transverse colon) #2 #1
kidneys

9. Steps of the digestive system

10. Step 1: food is chopped and ground in the mouth
AKA: Mechanical Digestion
Canines and incisors
Tear and shred food
Pre-molars and Molars
Mash food into a paste

11. Step 2: Saliva begins breaking down starches into simple sugars
Chemical digestion
Saliva changes complex carbohydrates into simple sugars
Food is now known as a “Bolus”

12. Step 3: The tongue muscles push the bolus down the esophagus
It’s called peri…what?!?!?!?
Food is moved by an involuntary wave-like motion called PERISTALSIS
Choke on this:
When food travels down the pharynx, the epiglottis closes over the larynx to prevent food from getting in your lungs!!

13. Step 4: Food enters the stomach through the esophagus
Chemical digestion
Done by HYDROCHLORIC ACID and PEPSIN
Mechanical digestion
Muscles in stomach “work” the food into a mixture called a CHYME

14. Step 5: Chyme now enters the small intestine
There’s nothing small about it!!
Is made of three parts
Duodenum
Jejunum
Illeum
1 inch diameter
10-24 feet long!!!!!
Nutrients are absorbed by villi
Taken through the body by cardiovascular system
Liver makes bile
Stored in gall bladder and released into small intestine

15. Step 6: Chyme mixture enters the large intestine
3 parts to the large intestine
Ascending colon
Transverse colon
Where water and vitamins are absorbed back in body
Descending colon
Where wastes enter the next step…..

16. Step 7: Waste is stored in the rectum until nature calls…
Now that all the “goodies” have been taken out of the food, we are left with fecal matter
Stored in rectum until a mixture of voluntary and involuntary muscle contractions (peristalsis) push it out
AKA…#2
Exits through the anus

17. Now that’s a “rap”!!!!!!!! http://www.youtube.com/watch?v=nj3KSnOTRH0