1. Ch 35 Guide Mechanical & Chemical Breakdown Of Food for energy
The Digestion System
Ch 35 Guide
Mechanical &
Chemical Breakdown
Of Food for energy

2. I 1) Mouth: Mechanically breaks up food Chemically digests
Carbohydrates
Basic pH
Enzyme amylase from salivary glands
Wets & forms “bolus”

3. 2. Stomach Mechanically churns Stores food Chemically digests Proteins
Acid pH
Enzyme Pepsin
From Pancreas
Mucus Lining prevents digestion of itself !
2. Stomach

4. 3. Small Intestine Absorption of food Digestion of Lipids (fats)
Carbohy-drates
Uses Lipase & Amylase from the pancreas
3. Small Intestine

5. 4. Large Intestine Absorbs water & vitamins No Digestion
Eliminates wastes

6. Barium Enema: window to the intestines:

7. 5. Salivary Glands: Makes the salivary juices Contains amylase enzymes
Basic pH
For the digestion of carbohydrates

8. 6 Liver:. Makes bile & Stores sugar as glucagon
No food passes through the liver
No digestion takes place in the liver
Gall Bladder stores bile

9. 7.Gall Bladder: Stores bile made by the liver
Bile emulsifies fats
Makes them water soluble
In small intestine
No food passes through the gall bladder
No digestion takes place in the gall bladder

10. Carter’s Little Liver Pills: cure=all
Liver also cleanses the blood
Carter’s pills claimed to cure constipation, headaches, skin problems???

11. 8.Pancreas makes digestive juices: Enzymes & Acids or bases
No Digestion in the Pancreas !
No food passes through here

12. 9. Appendix: vestigial organ

13. I 2-3. Types of Digestion: Intracellular: Extracellular: Inside a cell
Food vacuoles
Small particles
Examples:
Amoeba, Paramecium
Extracellular:
In a sack or tube
Larger food
Then absorbed into a cell
Humans

14. II. Digestion Products:
Proteins
Carbo-hydrates
Lipids
Amino acids subunits
Muscle,enzymes,Hb
Last use for food
Simple sugar (glucose)
Quick energy food
1st used
Fatty acids & glycerol
Long term food, insulation,protection
2nd used for food

15. III 1. Digestion: Is Breaking down food physically & chemically For
The purpose of distributing small water soluble particles to the cells for energy

16. III 2. Homeostasis Maintaining balance “homo”=same “stasis”=state
By constant adjustments
For survival

17. pH= Proper acid or base levels
Basic = > 7
Digestion of carbohydrates
& lipids
Acidic= < 7
Digestion of proteins in the stomach pH

18. 4.Properties of Enzymes Proteins Catalysts Speed reactions Work fast
Denature at high temp

19. Enzyme-Substrate complex
Active site =
where the
substrate
( reaction molecule)
connects to
enzyme
Active Site
Substrate
Enzyme

20. Lock & Key Model One enzyme for every substrate unique fit Enzyme

21. Enzymes are pH specific
Different enzymes
Different body areas
Different optimum pH
Stomach= acid pH
Uses PEPSIN
Mouth= basic pH
Uses AMYLASE
Blood
Mouth
Stomach

22. Bile: Made in Liver Stored in Gall Bladder
Emulsifies fats
Makes them water soluble
In small intestine

23. Villi: Small intestine absorb food
Many “finger-like” villi
maximize surface area

24. 8.Peristalsis: Contractions of the Digestive system Moves food down
Controlled by the autonomic nervous system

25. Control of Digestion by the Nervous System