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• What are the two main groups that make up amino acids?

  The amino group and the carboxyl group.
• What does it mean for amino acids to be amphoteric?

  They can act as both acids and bases.
• What is the exception among amino acids regarding chirality?

  Glycine is not a chiral molecule.
• What is an isoelectric point?

  It is the pH at which the overall charge of an amino acid is zero.
• How do amino acids exist as zwitterions?

  They have both a positive and a negative charge in the same molecule.
• What happens to the carboxylate ion at a low pH?

  It receives a proton and becomes a carboxylic acid.
• What occurs at a high pH regarding the amino group?

  The amino group loses a proton and becomes an amine.
• What technique is used to identify amino acids in a mixture?

  Thin layer chromatography (TLC).
• What is the role of the solvent in thin layer chromatography?

  The solvent helps to dissolve the amino acids and carry them up the plate.
• What must be done to visualize amino acids on the chromatogram?

  A dye or UV light is used to make the spots visible.
• How does iodine help in identifying amino acids on the chromatogram?

  Iodine vapor adheres to the amino acid spots, making them visible.
• What is the purpose of calculating RF values in chromatography?

  To identify amino acids by comparing their RF values to known substances.
• What factors must match when comparing RF values for amino acid identification?

  The temperature, solvent used, and TLC plate composition must match.
• What are proteins made of?

  Proteins are polymers made up of amino acids.
• What type of polymerization occurs when forming proteins?

  Condensation polymerization.
• What is released during the condensation polymerization of amino acids?

  Water is released.
• What is hydrolysis in the context of proteins?

  It is the process of breaking down proteins into amino acids using water.
• What conditions are required for hydrolysis of proteins?

  Six molar HCl, 110 degrees Celsius, and reflux for 24 hours.
• What is a dipeptide?

  A dipeptide is formed from two amino acids linked by a peptide bond.
• What happens to the peptide link during hydrolysis?

  The peptide link is broken to release individual amino acids.
• What is the significance of the carboxylic acid and amine groups in a dipeptide?

  They are present at either end of the dipeptide molecule.
• What concentration of HCl is required for the reaction described?

  Six molar HCl
• At what temperature must the reaction be conducted?

  110 degrees Celsius
• How long must the reaction be done under reflux?

  24 hours
• What happens to the peptide link during the process described?

  The bond in the middle of the peptide link is broken
• What do we add to the peptide link to form a carboxylic acid?

  OH (hydroxide)
• What do we add to the peptide link to form an amine?

  H (hydrogen)
• What are the three types of protein structures discussed?

  • Primary structure
  • Secondary structure
  • Tertiary structure
• What is the primary structure of a protein?

  The individual sequence of amino acids that make up the protein
• What is another name for a protein chain?

  Polypeptide chain
• What type of bonds exist in the secondary structure of proteins?

  Hydrogen bonds
• What are the two types of secondary structures in proteins?

  Alpha helix and beta pleated sheets
• What characterizes the tertiary structure of a protein?

  The coiled structure twists and turns into a unique shape
• What types of bonds hold the tertiary structure of proteins together?

  Hydrogen bonds, disulfide bonds, ionic interactions, and instantaneous dipole-induced dipole forces
• What is a disulfide bond in proteins?

  A bond formed between sulfur atoms from cysteine amino acids
• How do hydrogen bonds contribute to protein structure?

  They stabilize the coiled and folded shapes of the protein
• What effect do temperature and pH have on protein structure?

  They can change the shape of the protein by affecting bonds
• How do hair straighteners work on hair, which is a type of protein?

  They break bonds in the protein structure to straighten the hair
• What does DNA stand for?

  Deoxyribonucleic acid
• What is DNA made up of?

  Monomers called nucleotides