Protein molecule structures

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    Explain the difference between secondary and tertiary structure of protein molecules including reference to the type of bond involved

    Secondary refers the folding of the polypeptide chain involving hydrogen bonds into alpha helices or beta pleated sheets. Tertiary structures involve the final folding of the polypeptide chain to create its 3D shape. These involve hydrogen bonds, disulfide bridges, ionic bonds and hydrophilic/phobic interactions depending on the elements present in the R groups. For example, disulfide bridges form between two sulfur atoms, ionic form between two oppositely charged ions, and hydrogen ones form between a hydrogen atom and an electronegative element like F, O, N.

    Secondary structure of protein: this is when hydrogen bonds begin forming between amino acids in the polypeptide chains. The hydrogen bonds determine whether the protein folds into an alpha helix or a beta pleated sheet. In the secondary structure, disulfide bridges may also form and this occurs when 2 amino acids of cysteine come close together. The sulphur in one amino acid bonds with sulphur in the other cysteine and this forms disulfide bridges.
    Tertiary structure: more hydrogen bonds form between the amino acids in the polypeptide chains as well as ionic bonds, and the protein may fold or coil further. The tertiary structure forms the final 3D shape for proteins with a single polypeptide chain.

    since we are talking about biology, can anyone tell me how they rvised for application questions or how to get better at them?
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