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

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

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

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

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

Barium Enema: window to the intestines:

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

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

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

Carters Little Liver Pills: cure=all Liver also cleanses the blood Carters pills claimed to cure constipation, headaches, skin problems???

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

9. Appendix: vestigial organ

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

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

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

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

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

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

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

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

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

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

Villi: Small intestine absorb food Many finger-like villi maximize surface area

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

Control of Digestion by the Nervous System