Why are some amino acids classified as essential and others

Question

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1. Why are some amino acids classified as essential and others as nonessential?
2. What are complementary proteins? Give 2 examples.
3. What does the term limiting amino acid mean
4. How are the amino acids in a protein linked together?
5. Why is the structure of a protein important?
6. What effects does denaturation have on a protein?
7. What are 3 good sources of protein?
8. What are 3 ways of assessing protein quality?
9. What are 2 examples of proteins with high biological value (BV)?
10. What factors affect the protein quality of a food?
11. When is it important to be in positive nitrogen balance?
12. What situations increase the risk of being in negative nitrogen balance?
13. During what stage of the life cycle are people generally in nitrogen equilibrium?
14. Name 4 enzymes that are involved in protein digestion and absorption.
15. What are the end products of polypeptide digestion?
16. How is the absorption of proteins different in early infancy?
17. What are 3 functions of proteins?
18. How do proteins help maintain fluid balance?
19. How do proteins contribute to immune function?
20. How does kwashiorkor differ from marasmus?
21. Which individuals might be at greatest risk of PEM in the U.S.?
22. What areas of the world have the highest incidence of PEM?
23. Why might an excessive protein intake be harmful?
24. What are the symptoms of food allergies?
25. Which foods cause most food allergies?
26. What steps can parents take to help prevent food allergies in their children?
27. How does a vegan diet differ from a lacto-vegetarian diet?
28. Which nutrients are likely to be low in a vegan diet?
29. What are 2 nutritional risks for children on vegetarian diets?