1. Chapter 4 The Carbohydrates: Sugars, Starches, and Fibers

3. Carbohydrates  most abundant class of compounds found in nature  contain the elements C, H and O  term “CARBOHYDRATES” came from fact that these compounds could be written as “hydrates of carbon” e.g. C 6 H 12 O 6 = C 6 (H 2 O) 6

4. Simple Carbohydrates (sugars) Monosaccharides

5. Simple Carbohydrates (sugars) Monosaccharides

6. Simple Carbohydrates (sugars) Monosaccharides

7. Simple Carbohydrates (sugars) Disaccharides

8. Simple Carbohydrates (sugars) Disaccharides

9. Simple Carbohydrates (sugars) Disaccharides

10. Simple Carbohydrates (sugars) Disaccharides

11. Simple Carbohydrates (sugars) Disaccharides

12. Complex Carbohydrates Polysaccharides (glycogen, starches & fibres) Glycogen – energy storage in animals Starches – energy storage in plants Fibres – provides structure in plants

13. Complex Carbohydrates (glycogen versus starches)

14. Glycogen Starch (amylopectin) and (amylose) Animals Plants

15. Hydrolysis (breakdown) of Complex Carbohydrates Both glycogen and starches can be broken down by the human digestive system to give || Glucose

16. Major sources of starch include grains, legumes, and tubers. ©2001 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning ™ is a trademark used herein under license.

17. Starch and cellulose molecules compared (small segments)

18. Starch digestion in the GI Tract MOUTH: Starches are hydrolysed to smaller and smaller polysaccharides by enzymes referred to as AMYLASE. STOMACH: AMYLASE is deactivated due to acidic pH. SMALL INTESTINE: Pancreatic AMYLASE break starch polysaccharides down more and DISACCHARIDASES break down disaccharides.

19. Fiber in the GI Tract MOUTH: Fibers are mechanically ripped apart by teeth and moistened. NO ENZYME BREAKDOWN STOMACH and SMALL INTESTINE: NO ENZYME BREAKDOWN LARGE INTESTINE: Bacterial enzymes can break down small amounts of fiber…. FERMENTATION…. CAUSES GAS

20. Absorption of Monosaccharides Monosaccharides enter directly into the blood capillaries Glucose and Galactose are moved across cell membranes by ACTIVE TRANSPORT Fructose moves across my FACILITATED DIFFUSION Converted to GLUCOSE

21. The carbohydrates of grains, vegetables, fruits and legumes supply most of the energy in a healthful diet.

22. Maintaining blood glucose homeostasis ©2001 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning ™ is a trademark used herein under license.

25. Diabetes - related to the function of insulin to regulate glucose levels Type I (juvenile diabetes) Type 2 (adult diabetes)

26. ©2001 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning ™ is a trademark used herein under license. Foods rich in starch and fiber offer many health benefits.

27. ©2001 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning ™ is a trademark used herein under license. Carbohydrates on Food Labels

28. Structure of Artificial Sweeteners Saccharin (450 X) Cyclamate (30 X) Aspartame (180 X)

29. Hydrolysis of Aspartame

30. Sucralose

31. Sugar Replacers

32. Dental Caries (cavities) ©2001 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning ™ is a trademark used herein under license.