Week 4 Homework Flashcards
What is the primary purpose for the ribbon protein model?
portray the types of secondary structure
The structure of a protein dictates the partners with which it can interact. Therefore, the structure of a protein is directly related to its ___.
Function
The contours of a protein determine the ___ that its interaction partner must have, whereas the surface chemistry of a protein determines the kinds of chemical interactions that the protein will make with its interaction partner (e.g. Coulombic interactions or ___).
Shape, hydrogen bonding
Therefore, a protein will only bind to molecules that have the appropriate shape and chemistry (i.e. only those that are ___ the protein).
Complementary to
True or false? Attraction of hydrophobic residues to each other through weak dispersion forces drives aggregation of hydrophobic molecules in an aqueous environment.
False
True or false? Intramolecular hydrogen bonds stabilize folding of a polypeptide chain.
True
True or false? Salt bridges (ionic bonds) contribute to folding of a polypeptide chain.
True
True or false? Dipole-dipole interactions have a stabilizing, cumulative effect.
True
Which of the following pairs of amino acids would form the strongest noncovalent interaction in a protein? Assume the pH of the environment is 7.0. Refer to Figure 5.3 if you need help with the three letter amino acid abbreviations.
I. Ser and Lys
II. Asp and Gly
III. Thr and Asn
IV. Glu and Lys
IV
Compare the R group of tyrosine to the R group of phenylalanine. Which amino acid is most likely to be found in the interior of a protein.
Phenylalanine is more likely to be located in a protein’s interior because its R group is completely hydrophobic and nonpolar; the hydroxyl group in tyrosine’s R group gives it more polar uncharged character.
Compare the R group of serine to the R group of cysteine. Comparatively which R group is more polar?
Serine’s R group is more polar than cysteine because the O-H bond in serine is more polar than the S-H bond in cysteine.
True or false? Covalent bonds join amino acids together.
True
True or false? Amino acid properties determine what a protein looks like and what it does.
True
True or false? There is a limited range in the size and shape of proteins.
False
True or false? Only the α-carboxyl group in an amino acid can act as an acid.
False
True or false? A protein is a polymer and amino acids are the monomers.
True
Which functional groups can ionize in the side chain of an amino acid.
I. aldehyde
II. phosphoryl group
III. ketone
IV. carboxylic acid
V. amine
IV and V
