1. Changing Gly to Ala in the primary structure of a protein will always lead to a change in the overall shape of a protein.
a.) True
b.) False
2. An alpha helix:
a.) is stabilized by the amino acid proline
b.) can only form by hydrogen bonding between different polypeptide chains
c.) can only form when cysteines form disulfide bridges within this structure
d.) forms when side chains of D and E attract each other
e.) none of the above
3. What will likely happen if two histidines at pH 5 are next to each other in a polypeptide chain?
a.) The side chains of these amino acids will be uncharged and there will be no effect.
b.) The side chains of these amino acids will be charged and they will attract each other.
c.) The side chains of these amino acids will be charged and they will repel each other.
d.) Not enough information is given to determine the effect.
4.Consider the amino acid Tryptophan. Which of the following best describes where you predict this amino acid would be found?
a.) This amino acid is hydrophobic and would be on the surface of a protein that is in the middle
of a membrane.
b.) This amino acid is hydrophilic and would be on the surface of a protein that is in the middle
of a membrane.
c.) This amino acid is hydrophobic and would be in the interior of a protein that is in the middle
of a membrane.
d.) This amino acid is hydrophilic and would be in the interior of a protein that is in the middle of
a membrane.
e.) Not enough information is given to determine.
5. The difference between fetal and adult hemoglobin with regard to oxygen binding occurs because fetal hemoglobin has an amino acid substitution in one of its chains that results in a histidine being replaced by a serine.
a.) True
b.) False
