the digestion system ch 35 guide mechanical & chemical breakdown of food for energy
TRANSCRIPT
The Digestion System
Ch 35 GuideCh 35 Guide
Mechanical &Mechanical &
Chemical BreakdownChemical Breakdown
Of Food for energyOf Food for energy
I 1) Mouth: MechanicallyMechanically breaks up foodbreaks up food
ChemicallyChemically digests digests CarbohydratesCarbohydrates Basic pHBasic pH Enzyme amylase Enzyme amylase
from salivary from salivary glandsglands
Wets & formsWets & forms “bolus”“bolus”
2. StomachMechanicallyMechanically
churns churns Stores Stores foodfoodChemicallyChemically
digestsdigests ProteinsProteins Acid pHAcid pH Enzyme PepsinEnzyme Pepsin From PancreasFrom PancreasMucus Lining Mucus Lining
prevents digestion prevents digestion of itself !of itself !
3. Small Intestine AbsorptionAbsorption
of foodof food
Digestion Digestion ofof Lipids (fats)Lipids (fats) Carbohy-Carbohy-
dratesdratesUses Lipase & Uses Lipase &
Amylase from Amylase from the pancreasthe pancreas
4. Large Intestine
Absorbs Absorbs water & water & vitaminsvitamins
No DigestionNo DigestionEliminates Eliminates
wasteswastes
Barium Enema: window to the intestines:
5. Salivary Glands: MakesMakes the the salivary juicessalivary juices
Contains Contains amylase amylase enzymesenzymes
Basic pHBasic pH For the For the
digestion of digestion of carbohydratescarbohydrates
6 Liver:. Makes bile & Stores sugar as glucagon
No food passes through the liverNo digestion takes place in the liver
Gall Bladder stores bile
7.Gall Bladder: Stores bile made by the liver
Bile emulsifies Bile emulsifies fatsfats
Makes them Makes them water solublewater soluble
In small In small intestineintestine
No food passes through the gall bladderNo digestion takes place in the gall bladder
Carter’s Little Liver Pills: cure=all
Liver also Liver also cleanses the cleanses the bloodblood
Carter’s pills Carter’s pills claimed to cure claimed to cure constipation, constipation, headaches, skin headaches, skin problems???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:Intracellular: Inside a cellInside a cell Food vacuolesFood vacuoles Small particlesSmall particles Examples:Examples: Amoeba, Amoeba,
ParameciumParamecium
Extracellular:Extracellular: In a sack or In a sack or
tubetube Larger foodLarger food Then absorbed Then absorbed
into a cellinto a cell HumansHumans
II. Digestion Products:ProteinsProteins
Carbo-Carbo-hydrateshydrates
LipidsLipids
Amino acidsAmino acids subunits subunits Muscle,enzymes,HbMuscle,enzymes,Hb Last use for foodLast use for food
Simple sugar (glucose)Simple sugar (glucose) Quick energy foodQuick energy food 11stst used used
Fatty acids & glycerolFatty acids & glycerol Long term food, Long term food,
insulation,protectioninsulation,protection 22ndnd used for food used for food
III 1. Digestion:IsIs Breaking down foodBreaking down food physically & chemicallyphysically & chemically
ForFor The purpose of distributing small The purpose of distributing small
water soluble particles to the cells water soluble particles to the cells for energyfor energy
III 2. Homeostasis Maintaining Maintaining
balancebalance ““homo”=samehomo”=same ““stasis”=statestasis”=state By constant By constant
adjustmentsadjustments For survivalFor survival
pH= Proper acid or base levels
Basic Basic = > 7 = > 7 Digestion of Digestion of
carbohydratescarbohydrates & lipids& lipids AcidicAcidic= < 7= < 7 Digestion of Digestion of
proteins in the proteins in the stomachstomach pH 2 7 8 1 0 12
4.Properties of Enzymes ProteinsProteins CatalystsCatalysts Speed reactionsSpeed reactions Work fastWork fast Denature at high Denature at high
temptemp
Enzyme-Substrate complex
Substrate
Active site = where the substrate( reaction molecule)connects toenzyme
Active Site
Enzyme
Lock & Key ModelOne One enzymeenzymefor every for every
substratesubstrateunique fitunique fit
Substrate
Enzyme
Enzymes are pH specific
Different enzymesDifferent enzymes Different body areasDifferent body areas Different optimum pHDifferent optimum pH
StomachStomach= acid pH= acid pH
Uses Uses PEPSINPEPSIN
MouthMouth= basic pH= basic pH
Uses Uses AMYLASEAMYLASE0
10
20
30
40
50
60
70
80
90
100
pH 2 pH 4 Ph 6 pH 8
Stomach
Blood
Mouth
Bile: Made in Liver Stored in Gall Bladder
Emulsifies Emulsifies fatsfats
Makes them Makes them water solublewater soluble
In small In small intestineintestine
Villi: Small intestine absorb food
Many “finger-like” villi maximize surface area
8.Peristalsis: ContractionsContractions
of the of the Digestive Digestive system system
Moves foodMoves food downdown
Controlled by Controlled by the autonomic the autonomic nervous nervous systemsystem
Control of Digestion by the Nervous System