3.3.13.1 Amino Acids

• What determines the overall characteristics of an amino acid?

  Properties of the R group
• Aromatic R groups can participate in hydrophobic interactions.


  True
• Match the type of R group with an example:

  Nonpolar Aliphatic ↔️ Glycine

  Aromatic ↔️ Tryptophan

  Polar Uncharged ↔️ Serine

  Positively Charged ↔️ Lysine

  Negatively Charged ↔️ Aspartic acid
• What is attached to the alpha carbon of an amino acid along with the amino and carboxyl groups?

  R group
• Aromatic R groups are nonpolar and can participate in hydrophobic interactions.
• Match the R group type with its example:

  Nonpolar Aliphatic ↔️ Glycine

  Aromatic ↔️ Phenylalanine

  Polar Uncharged ↔️ Serine

  Positively Charged ↔️ Lysine

  Negatively Charged ↔️ Aspartic acid
• Why are zwitterions considered amphoteric?

  Act as acids and bases
• Amino acids link together through peptide bonds to form polypeptide chains.
• The R group is attached to the alpha carbon along with the amino and carboxyl groups.
• Nonpolar aliphatic R groups are hydrophobic and non-reactive.
• Arrange the following types of R groups based on increasing polarity:

  1️⃣ Nonpolar Aliphatic

  2️⃣ Aromatic

  3️⃣ Polar Uncharged

  4️⃣ Positively Charged

  5️⃣ Negatively Charged
• The R group is attached to the alpha carbon along with the amino and carboxyl groups.
• The R group of an amino acid is also known as the side chain.

  True
• Which type of R group helps maintain protein structure and binds DNA?

  Positively charged
• Amino acids can exist as zwitterions, which carry both positive and negative charges.
• Match the type of amino acid with its example:

  Essential ↔️ Lysine

  Non-essential ↔️ Alanine
• What two functional groups are present in all amino acids?

  Amino and carboxyl groups
• Match the type of R group with its properties:

  Nonpolar, Aliphatic ↔️ Hydrophobic, non-reactive

  Aromatic ↔️ Nonpolar, hydrophobic interactions

  Polar, Uncharged ↔️ Hydrophilic, hydrogen bonds

  Positively Charged ↔️ Basic, hydrophilic

  Negatively Charged ↔️ Acidic, hydrophilic
• What type of bond can polar uncharged R groups form?

  Hydrogen bonds
• The alpha carbon in an amino acid is bonded to the amino group, carboxyl group, hydrogen, and the R group.


  True
• The properties of the R group determine the overall characteristics of each amino acid.
• Polar, uncharged R groups can form hydrogen bonds.


  True
• Amino acids are classified based on their R group properties.


  True
• Essential amino acids can be synthesized by the human body.

  False
• What determines the structure and function of a protein?

  Amino acid sequence