CHAPTER 4 HOMEWORK PROTEIN STRUCTURE
1. The primary structure of a protein refers to: a) the order in which the amino acids are bonded together in a polypeptide chain. B) the cofactors and other prosthetic groups found in the protein c) The folding pattern observed in the protein d) The a
angement of polypeptide chains in the protein, if it has more than one.
2. Peptide bonds cannot rotate. This is because: a) the amino acid side chains are too bulky to allow this. B) Internal hydrogen bonding hinders rotation. C) interaction with water molecules hinders rotation D) the peptide bond has considerable double bond characte
3. Polypeptide chains prefer the trans conformation. This is because: a) This distances hydrophilic groups from hydrophobic groups b) this minimizes crowding of side chains c) This
ings hydrophilic groups in contact with water molecules d) This allows proteins to fold more easily
4. Ramachandran plots indicate that protein conformation is largely a function of: a) hydrophobicity b) number of amino acids c) torsion angles d) a
angement of prosthetic groups
5. Which of these is a description of secondary structure? A) insulin has 50 amino acids b) Insulin has several alpha helical segments c) insulin has a folded globular structure d) insulin has 2 polypeptide chains
6. Motifs are recognizable patterns of: a) primary structure b) secondary structure c) tertiary structure d) quaternary structure
7. Domains are recognizable patterns of: a) primary structure b) secondary structure c) tertiary structure d) quaternary structure
8. Subunits differ from domains because: a) subunits are connected by peptide bonds while domains are not b) domains are connected by peptide bonds while subunits are not c) domains are larger than subunits d) subunits are larger than domains
9. Beta ba
el is a type of: a) subunit b) motif c) domain d) transport protein
10. The major secondary structure seen in collagen is: a) alpha helix b) beta sheet c) collagen helix d) random coil or nonrepetitive
11. The major secondary structure seen in hemoglobin is: a) alpha helix b) beta sheet c) collagen helix d) random coil or nonrepetitive
12. Although all of these play a part in protein folding, the one which contributes the most is: a) salt
idges b) hydrogen bonds c) Van der Waals interactions d) hydrophobic effect
13. An intermediate folding stage seen in protein denaturation or renaturation is called : a) domain b) motif c) subunit d) molten globule
14. Proteins which do not renature spontaneously when denaturation conditions are removed may need the assistance of: a) a prosthetic group b) a higher salt concentration c) a lower temperature d) a chaperone protein
15. The information needed for co
ect protein folding is encoded in: a) the su
ounding molecules b) the protein’s amino acid sequence c) the pH of the aqueous medium d) the electrolyte composition of the aqueous solution