Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

29. Amino Acids

Proteins and Amino Acids

Organic Chemistry

29. Amino Acids

Proteins and Amino Acids

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Multiple Choice

In which way do the structures of amino acids differ from each other?

The side chain (R group) attached to the alpha carbon

The presence of a carboxyl group

The presence of a hydrogen atom

The presence of an amino group

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Verified step by step guidance

Understand the basic structure of an amino acid: Each amino acid has a central alpha carbon (C_α) to which four different groups are attached: an amino group (-NH₂), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain (R group).

Recognize that the amino group, carboxyl group, and hydrogen atom are common to all amino acids. These groups do not vary between different amino acids.

Focus on the side chain (R group): The R group is the variable part of the amino acid structure. It is this group that differs among the 20 standard amino acids, giving each one its unique properties.

Consider the role of the R group: The chemical nature of the R group (e.g., size, charge, hydrophobicity, reactivity) influences the amino acid's characteristics and its role in protein structure and function.

Conclude that the primary structural difference between amino acids is the side chain (R group) attached to the alpha carbon, as this is the only component that varies among different amino acids.