AP Biology / Unit 1: Chemistry of Life
1.7 Proteins
Notes
Proteins are chains of amino acids joined by peptide bonds. The R group gives each amino acid its properties.
- Primary: amino acid sequence. Secondary: α-helices and β-sheets (backbone H-bonds).
- Tertiary: 3D folding from R-group interactions. Quaternary: multiple chains.
Practice
A change in one amino acid can change a protein's function because:
Sequence determines shape.
α-helices and β-sheets are levels of:
Backbone hydrogen bonding.
Hemoglobin has four polypeptide chains. This is:
Multiple subunits.
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