AP Bio - Proteins

Primary Structure

Primary Structure is when DNA provides information for amino acid chains using peptide bonds at the ribosome.

Secondary Structure

Secondary Structure is when local folding occurs using Hydrogen bonds establishing 3D shape. The 3D structures can either be Alpha Helix (right handed spiral) or Beta Pleated Sheet (flat sheet like).

Tertiary Structure

Tertiary Structure uses long distance folding to complete the proteins form. Most proteins become functional at this stage and become stabilized using covalent bonds, hydrogen bonds, ionic bonds, and london dispersion forces.

Quaternary Structure

Quaternary Structure uses polypeptide to polypeptide interactions using hydrophilic and hydrophobic interactions. Can be disrupted by adverse salinity (salt), PH, or temperature by making the protein denature. It doesn’t happen for all proteins.