education grade 7

1. By/ Amel Hanafi

2. Digetive system functions
Food undergoes three types of processes in the body
1- Digestion
2- Absorption
3-Elimination

3. Structure of digestive system

4. 1-Mouth
 Mechanical digestion
 Chemical digestion
 Tongue and different
shaped teeth work
together to break down
food mechanically

5. 2- Esophagus
 No digestion
 Transport food from throat to the stomach

6. 3-Stomach
 Mechanical and chemical
digestion
 Two sphincters
Cardiac –Pyloric sphincters
 Starts protein digestion
 Secrets gastric juices contain
a-hydrochloric acid
b-enzymes included
Pepsinogen and Rennin

7. 4-small intestine
 digestion completed
 Absorption of nutrients occurs
 Intestinal enzymes
1-amylases
2-peptidases(proteases)
3-nucleases
4-lipases

8. VILLI
 Finger like projections line the
small intestine and absorb all
the nutrients released from
digested food
 Villus has:
1-capillaries absorb nutrients
directly to blood
2-lacteal absorbs fatty acids and
glycerol into lymphatic system
3-microvilli appendages enhance
rate of absorption

9. 5-Liver
 Produce bile that emulsifies fats
 Send bile to gall bladder until
release it into small intestine
 Neutralize chyme(acidified food
from stomach)entering the
small intestine
 Detoxifies blood
 Produce cholesterol
 Produce nitrogenous wastes
 Breaks down and recycle RBCs

10. 6-Gall bladder 7-Pancrease
 Store bile produced by liver
 Bile emulsifies fats in small
intestine
 Body can function well
without gall bladder
 Secrets peptidases
 (protein digesting enzymes)
into small intestine

11. 8-Large intestine
 No digestion occurs here
 Have 3 major functions
 Egestion
 Vitamin production
 Reabsorption of water

12. Test your self

13. THANKS