Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
The Digestion System Ch 38-2 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” Esophagus Bolus movement to stomach by peristalsis (see video) 2. Stomach Mechanically churns Stores food Chemically digests Acid pH Proteins Enzyme Pepsin Mucus Lining prevents digestion of itself ! 3. Small Intestine Absorption of food Digestion of Lipids (fats) Carbohydrates 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 glycogen 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 Carter’s Little Liver Pills: cure=all Liver also cleanses the blood Carter’s 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 Types of Digestion: Intracellular: Inside a cell Food vacuoles Small particles Examples: Amoeba, Paramecium Extracellular: In a sack or tube Larger food Then absorbed into a cell Humans 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 Digestion: Is Breaking down food physically & chemically For The purpose of distributing small water soluble particles to the cells for energy Homeostasis Maintaining balance “homo”=same “stasis”=state By constant adjustments For survival pH= Proper acid or base levels Basic =>7 Digestion of carbohydrates & lipids Acidic= < 7 Digestion of proteins in the stomach pH 2 7 8 10 12 Properties of Enzymes Proteins Catalysts Speed reactions Work fast Denature at high temp Enzyme-Substrate complex Active site = where the substrate ( reaction molecule) connects to enzyme Active Site Substrate Enzyme Lock & Key Model One Substrate enzyme for every substrate unique fit Enzyme Enzymes are pH specific Different enzymes Different body areas Different optimum pH Stomach= acid pH Uses PEPSIN Mouth= basic pH Uses AMYLASE 100 90 80 70 Blood 60 50 40 30 20 10 Stomach Mouth 0 pH 2 pH 4 Ph 6 pH 8 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