Notes on Biomolecules and Functional Groups

Biomolecules

• Biomolecules are organic molecules containing carbon-to-carbon or carbon-to-hydrogen bonds.
• Carbon can bind with hydrogen, oxygen, nitrogen, phosphorus, and sulfur.
• Carbon can form chains, branched chains, and ring structures, and double bonds.
• The carbon chain of a biomolecule is its skeleton or backbone.

Functional Groups

• Functional group: a specific group of bonded atoms with the same chemical properties that reacts the same way.
• Common functional groups: hydroxyl, carboxyl, amino, sulfhydryl, and phosphate groups.
• Functional groups determine the identity and chemical reactivity of the biomolecule.
  • Example: A carboxyl group attached to a carbon backbone forms a fatty acid.
  • Example: An amino group and a carboxyl group attached to a carbon backbone form an amino acid.

Biomolecule Classes

• Four classes: proteins, carbohydrates, nucleic acids, and lipids.