Midterm 1 Old Exams/Study Questions Flashcards
- Which of the following amino acids would you find in a “turn” of the polypeptide backbone?
a. Tryptophan
b. Proline
c. Phenylalanine
d. Histidine
e. glycine
f. b and e
f. b and e (proline and glycine)
What kind of noncovalent interaction is typified by interactions between two molecules that
are so close together that they can experience weak attractive forces bonding them together?
van der Waals forces
- A disulfide bond in a protein usually exists:
outside the cell because the environment outside the cell is oxidizing
- Which of the following is not a macromolecule formed by polymerization?
a. proteins
b. lipids
c. polynucleotides
d. polysaccharides
e. DNA
b. lipids
- Monomeric proteins do not contain a:
a. primary structure.
b. secondary structure.
c. tertiary structure.
d. quaternary structure.
d. quarternary structure
- Which amino acid is most likely to be found in the core of a protein?
a. methionine
b. asparagines
c. serine
d. threonine
e. glutamic acid
methionine
- The α-helix is characterized by orientation of ______ the molecular axis.
a. H bonds parallel to
b. H bonds perpendicular to
c. ionic bonds parallel to
d. ionic bonds perpendicular to
e. peptide bonds perpendicular to
H bond parallel to
- Which amino acid is most likely located on the surface of a native protein in aqueous solution?
a. Phenylalanine
b. Isoleucine
c. Asparagine
d. Tryptophan
e. None of the above
c. Asparagine
- Which of the following is not a model organism?
a. Mice
b. Fruit fly
c. Roundworm
d. Yeast
e. Human
f. Bacteria
e. human
- When two atoms differing in electronegativity are joined in a covalent bond, then the
a. electrons are shared equally between the atoms.
b. bond is nonpolar.
c. resulting compound is devoid of any dipole moment.
d. atom with the greater electronegativity attracts the bonded electrons more.
d. atom with greater electronegativity attracts the bonded electrons more
- Which of the following is a mechanism for regulating protein activity?
a. proteolytic processing
b. phosphorylation/dephosphorylation
c. ligand binding
d. b and c
e. all of the above
e. all of the above
- Which are amino acids used in the kinase/phosphatase switch?
a. serine
b. threonine
c. tyrosine
d. a and b
e. a, b and c
e. serine, threonine, and tyrosine
14. What kind of enzyme adds phosphate groups to enzymes for the purpose of activating or deactivating them? a. phosphatases b. protein kinases c. flippases d. glycosyltransferases
protein kinases
– are mirror images. They have similar chemical properties but different
biological properties.
Stereoisomers
What kind of enzyme adds phosphate groups to proteins for the purpose of activating or deactivating them?
protein kinases