1. Digestion and Absorption Johnson Chap. 34-35 Jack L. Leonard 2004

2. Johnson Chap. 34-35 Epithelial Cell Structure

3. Johnson Chap. 34-35 Cell membrane Glycocalyx Transport carrier ExtrinsicenzymeIntrinsicenzymeMicrovillus

4. Johnson Chap. 34-35 1,4 link 1,6 link  -limit dextrins  amylase maltotriose maltose amylopectin Initial breakdown of starch

5. Johnson Chap. 34-35 Amylose

6. Amylopectin

7. Cellulose

8. Sucrose

9. Lactose

10. Maltose

11. glucose galactose fructose sucrose lactose  -limit dextrins (G5-G9) Malto-oligosaccharides Starchglycogen  amylase glucose Glucosetransporter Na + G GaGF G-G-G-G G-G-G 40% G 2 25% G 3 5% G 4 -G 9 Lactase Glucosecarrier Fructosecarrier Sucrase  -dextrinase Glucosecarrier Glucoamylase Brush Border CHO enzymes

12. Johnson Chap. 34-35 Enzyme Primary Action Endopeptidases Hydrolyze(s) interior peptide bonds containing Pepsin Pepsin Aromatic amino acids Trypsin Trypsin Basic amino acids Chymotrypsin Chymotrypsin Aromatic amino acids—leu, met, gln—C-terminal residue Elastase Elastase Neutral aliphatic amino acids Exopeptidases Hydrolyze(s) external peptide bonds containing Carboxypeptidase A Carboxypeptidase A Aromatic and neutral amino acids—aliphatic AA at C-terminus Carboxypeptidase B Carboxypeptidase B Aromatic and neutral amino acids—basic AA at C-terminus Principal luminal proteases

13. Johnson Chap. 34-35 Principal luminal absorption

14. Johnson Chap. 34-35 Intact Protein Absorption

15. Johnson Chap. 34-35 Principal luminal absorption

16. Johnson Chap. 34-35 http://www.colorado.edu/epob/epob1220lynch/image Digestion of Fat

17. Johnson Chap. 34-35 http://www.rpi.edu/dept/chem-eng/Biotech-Environ/Membranes/bauerp Absorption of Sugars

18. Johnson Chap. 34-35 Carrier AA transported Neutral (  -amino- monocarboxylic) Aromatic (Phe, Tyr, Trp) Aliphatic (Gly, Ala, Val, Leu, Ile, Ser His, Met, Asn, Gln, Cys, Pro, OH-Pro Basic (cationic) Lys, Arg, Orn, Cys Acidic (anionic) Glu, Asp, SeC Imino Pro, OH-Pro, GABA, Tau, Gly, other AA with amino groups in  or  positions Amino Acid Carrier Systems

19. Johnson Chap. 34-35 Absorption of Fluid and Ions Cl K+K+K+K+ ATP Na + Lumen Serosal surface glucose Na + K+K+K+K+ ATP H+H+H+H+ + HCO 3 - H+H+H+H+ H 2 CO 3 H2OH2OH2OH2O CO 2 + CO 2 metabolism + HCO 3 - H+H+H+H+ H 2 CO 3 H2OH2OH2OH2O CO 2 + HCO 3 - Cl -

20. Johnson Chap. 34-35 Na ~ ~ ~ H K Na K K [K~155 mM] 32 mV Na - + 56 mV - + 41 mV 47 mV -15 mV + - Serosa Mucosa