1. Chapter 6 The Proteins and Amino Acids Nutrition: Concepts & Controversies, 12e Sizer/Whitney

2. The Structure of Proteins  Difference from carbohydrates and fats  Amino acids  Carbon atom with amine group and acid group  Side chain  Essential amino acids  Conditionally essential  Recycling  Priority system

3. How Do Amino Acids Build Proteins?  Peptide bonds  Link amino acids  Strands of amino acids do not remain straight  Coils  Folds  Side chain electrical charge  Activation

4. The Coiling and Folding of a Protein Molecule

5. The Structure of Hemoglobin

6. Normal Red Blood Cells and Sickle Cells

7. Protein Synthesis

8. Denaturation of Proteins  Denaturing agents  Digestion  Stomach acid  Dangers of denaturation

9. Protein Digestion  Stomach  Denatures protein in food  Uncoil protein’s strands  Enzymes attack peptide bonds  Small intestine  Polypeptides  Further break down  Common misconceptions

10. A Dipeptide and Tripeptide

11. How Protein in Food Becomes Amino Acids in the Body

12. Amino Acid Absorption  Absorbed by cells of small intestine  Larger molecules  Hormones or allergens  Separate sites for absorption  Released into the bloodstream  Carried to the liver

13. The Importance of Protein  Amino acids must be continually available  Building of new proteins  Amino acids are needed each day  Protein turnover

14. Roles of Body Proteins  Regulation of gene expression  Providing structure and movement  Muscle tissue  Other structural proteins  Building enzymes, hormones, & other compounds  Building antibodies

15. Enzyme Action

16. Amino Acid Sequence of Human Insulin

17. Roles of Body Proteins  Transporting substances  Hemoglobin and lipoproteins  Maintaining fluid and electrolyte balance  Edema  Maintaining acid-base balance  Blood clotting  Providing energy and glucose

18. Proteins Transport Substances Into and Out of Cells

19. Amino Acids to Glucose  Protein can help maintain blood glucose levels  No storage compound for protein  Dismantle tissue proteins  Oversupply of amino acids  Remove amine group  Use of residues

20. Three Different Energy Sources

21. Amino Acids to Glucose  Fate of an amino acid  Cellular use  Build protein  Make a needed compound  Dismantle amino acid for component parts  Wasting of amino acids  Preventing waste

22. People Most Likely to Be Harmed by Amino Acid Supplements

23. How Much Protein Do People Really Need?  DRI  Depends on body size  Infants and growing children  Recommended intake  Vegetarians  Minimum amount  Upper limit  Body’s health  Quality

24. Nitrogen Balance  Nitrogen excreted as compared to nitrogen eaten  Levels in healthy adults  Variation in nitrogen balance  Positive balance  Examples  Negative balance  Examples

25. Which Foods Provide High Quality Protein?  High-quality proteins  Enough of all essential amino acids  Limiting amino acids  Complementary proteins  Mutual supplementation  Protein digestibility  Animal proteins  Legumes

26. A Legume