13.1 chemistry of digestion: carbohydrates
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13.1 Chemistry of Digestion: Carbohydrates. Digestion is the hydrolysis of food molecules to small molecules for absorption and utilization by cells for energy and other metabolic needs. Figure 21-6: Carbohydrate digestion. Chemistry of Digestion: Carbohydrates. Starts in mouth. - PowerPoint PPT PresentationTRANSCRIPT
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13.1 Chemistry of Digestion: Carbohydrates13.1 Chemistry of Digestion: Carbohydrates
Figure 21-6: Carbohydrate digestion
Digestion is the hydrolysis of food molecules to small molecules for absorption and utilization by cells for energy and other metabolic needs.
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Chemistry of Digestion: CarbohydratesChemistry of Digestion: Carbohydrates
• Polysaccharides
• Disaccharides
• Monosaccharide
• (Absorption)
animation
Starts in mouth
Completed in small intestine
Nothing happens in the stomach because it is too
acidic.
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Chemistry of Digestion: CarbohydratesChemistry of Digestion: Carbohydrates
Figure 21-6: Carbohydrate digestion
MouthSmall intestine
Blood
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Fig. 13.2
Summary of carbohydrate digestion in the human body.
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Fig. 13.3
An overview of glycolysis.
see handout
13.2 Glycolysis
KNOW for all 10 reactions:
← Structures and names of carbohydrates and metabolites
← Symbols of all cofactors
← Reaction types
← Enzyme names
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Table 24.1
Summary of ATP production from glucose in glycolysisSummary of ATP production from glucose in glycolysis
6 2(glyceraldehyde-3-phosphate1,3-bisphosphoglycerate 2NADH
3 ATP
total ATP from glycolysis 5 ATP
Each NADH in cytosol eventually yields 1.5 ATP (see the next slide)
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Fig. 13.8
The dihyroxyacetone phosphate-glycerol 3-phosphate shuttle to.
Each FADH2 yields 1.5 ATP in the ETC
ETC
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Regulation of glycolysis
Rxn 1. Glucose-6-phosphate inhibits this step
Rxn 3. ATP inhibits this step
Rxn 10. ATP inhibits this step
13.2 Glycolysis (cont.)
Note: 1.A ll enzymes that are regulated are “kinase” enzymes.
2.High levels of ATP (low bodily energy use) inhibits glycolysis.
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13.3 Fates of pyruvate13.3 Fates of pyruvate
Fig. 13.6
The three common fates of pyruvate generated by glycolysis.
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← Fig. 13.7
All three of the common fates of pyruvate from glycolysis provide for the regeneration of NAD+ from NADH.
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Fig. 13.10 Pyruvate also makes oxaloacetate
Oxaloacetate is involved in both gluconeogenesis and the Krebs cycle.
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• NADH from pyruvate acetyl-CoA yields
• 5 ATP in the mitochondrial matrix
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Page 470. Summary of glucose metabolismPage 470. Summary of glucose metabolism
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• Total ATP from metabolism of glucose
C6H12O6 + O2 6CO2 + 6H2O
• Glycolysis 5 ATP
• Pyruvate 5 ATP
• Krebs cycle 20 ATP
30 ATP
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Fig. 13.13 The relationships among four common metabolic pathways that involve glucose.
oxaloacetate
Krebs cycle
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Page 470. Summary of glucose metabolismPage 470. Summary of glucose metabolism