Question

1) Select all that apply. Globular proteins:

a)are found in hair and wool.

b)include myoglobin and collagen.

c)are usually water soluble.

d)aggregate in aqueous media.

e)are often made of β-pleated sheet and α-helix sections wrapped into compact structures.

2) Select all that apply. The Bohr effect:

a)depends on the atomic orbital structure of hydrogen.

b)can be summarized as a reduction in the oxygen affinity of hemoglobin with decreasing pH.

c)is explained by the protonation of key amino acids, including the N-termini of the α-chains and His¹⁴⁶ of the β-chains.

d)describes the manner in which the oxygen-binding ability of myoglobin is affected by the presence of H⁺ and CO₂.

e)explains how pH-based changes in the quaternary structure of hemoglobin can modulate the buffering of blood

3)Select all that apply. The resonance structure developed by two peptide-bonded amino acids:

a)leads to an electric dipole moment pointing perpendicular to the direction of the peptide bond.

b)increases the strength of the bond, so it has partial double bond character.

c)plays an important role in determining how a protein backbone can fold.

d)is a consequence of electrons shifting in position.

e)results in reduced rotation around the C-N bond of the planar peptide group.

4)Select all that apply. Hydrophobic interactions:

a)in proteins are driven mostly by attractive forces between nonpolar amino acid side groups.

b)cause proteins to fold so that nonpolar hydrophobic side chains are sequestered in the interior of the protein.

c)are a spontaneous process.

d)are a major factor in the folding of proteins into their native conformations.

e)increase the entropy of the universe.

5)Select all that apply. Chaperone proteins:

a)bind potentially toxic molecules to sequester them.

b)assist in the transport of secreted proteins from the ribosome to the plasma membrane.

c)aid in the correct folding of other proteins.

d)are incorrectly folded proteins.

e)keep partially translated proteins from folding incorrectly before they are finished.

Answer 1

Answer

1) option c is the right answer as globular proteins are normally water soluble in which hydrophilic amino acid arranged around the surface of the protein .

2) Options b and e is the right answer as Bhor's effect explains the reduced oxygen-binding affinity of hemoglobin under acidic pH.

3) Options b d and e is the right answer

4) Option b c and d is the right answer