10 marker questions

Question 1

discuss the role of amino acid r groups in
a) the determination of tertiary structure of proteins
b) influencing the location of proteins within cells

Answer 1

a)
- tertiary structure is a folded polypeptide
- the conformation is determined by the r group interactions and the primary structure
- r group classifications include acidic, basic, polar and hyrophobic
- the interactions between the groups include ionic bonds, hydrogen bonds, and disulfide bridges

b)

• polar groups are mostly at the surface of a soluble protein
• soluble proteins are found in the cytoplasm
• hydrophobic groups cluster at the centre of the protein
• membrane proteins can be integral or peripheral
• some integral proteins are transmembrane and include receptors and channels
• hydrophilic r groups interact with the extracellular environment.
• peripheral proteins have fewer hydrophobic r groups interacting with the phospholipids