Protein Structure MCQs : This section focuses on the "Protein Structure". These Multiple Choice Questions (MCQs) should be practiced to improve the Protein Structure skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
BRACl, an inherited form of breast cancer, regulates cell division by
A. binding to a DNA sequence
B. complexing with cyclins
C. binding to the cell outer membrane
D. binding to the protein RAD 51 which repairs DNA damage
Question 2
Metastasis involves
A. ability of cells to dissolve cellular matrix
B. metalloprotein levels
C. decreased levels of proteins that regulate metalloproteins
D. all of the above
Question 3
Individuals with PKU disease are mentally retarded unless
A. phenylalanine in the diet is restricted
B. tyrosine in the diet is restricted
C. homogentisic acid in the diet is restricted
D. none of the above
Question 4
Sickle cell disease is due to
A. a mutation in the beta chain of Hb
B. a mutation in the alpha chain of Hb
C. infection with a parasite
D. none of the above
Question 5
Over 50% of common cancers are associated with damage to a protein, p53. This protein
A. is a cyclin
B. is a tumor supressor
C. is an oncogene
D. regulates apoptosis
Question 6
Protein folding is
A. automatic, mediated by the protein itself
B. mediated by other proteins called chaperones
C. mediated by the ribosomes
D. none of the above
Question 7
Marfan's syndrome is thought to be a mutation affecting
A. hemoglobin synthesis
B. collagen synthesis
C. metabolism of homogentisic acid
D. insufficient thyroid production
Question 8
Cyclins are proteins that
A. regulate ability of cells to invade tissue
B. regulate passage from one stage of cell division to another
C. regulate apoptosis of damaged cells
D. none of the above
Question 9
Beta pleated sheets are examples of protein's
A. primary structure
B. secondary structure
C. tertiary structure
D. quaternary structure
Question 10
The four subunits of the hemoglobin (Hb) gene represent protein's
A. primary structure
B. secondary structure
C. tertiary structure
D. quaternary structure
Question 11
Signal sequences are part of a protein that
A. signal folding of the protein
B. signal the protein synthesis on the ribosomes is ended
C. transport proteins to other sites within the cell
D. refold proteins in prion-associated diseases
Question 12
A coiled peptide chain held in place by hydrogen bonding between peptide bonds in the same chain is?
A. Primary structure
B. α-helix
C. β-pleated sheets
D. Tertiary structure
Question 13
A structure that has hydrogen bonds between polypeptide chains arranged side by side is?
A. Primary structure
B. α-helix
C. β-pleated sheets
D. Tertiary structure
Question 14
Secondary structure is defined by _________
A. Hydrogen bonding
B. Vander Waals forces
C. Covalent bonding
D. Ionic bonding
Question 15
Which of the following are known as helix breakers?
A. Proline and glycine
B. Isoleucine and leucine
C. Valine
D. Threonine
Question 16
Which of the following does not affect the stability of an α-helix?
A. Electrostatic repulsion
B. Bulkiness
C. Interaction between R groups spaced three residues apart
D. Occurrence of alanine and glycine residues
Question 17
Which of the following is a false statement?
A. α-Keratin is α helical
B. Collagen is α helical
C. Hemoglobin has a quaternary structure
D. α-Keratin is β pleated structure
Question 18
Which of the following is false about NMR spectroscopy?
A. NMR is an abbreviated form of Nuclear Magnetic Resonance
B. The intramolecular magnetic field around an atom in a molecule changes the resonance frequency giving structural information about the atom
C. The intermolecular magnetic field around an atom in a molecule changes the resonance frequency giving structural information about the atom
D. It is a technique that exploits magnetic properties of atomic nuclei
Question 19
Which of the following is not true about secondary protein structure?
A. The hydrophilic/hydrophobic character of amino acid residues is important to secondary structure
B. The ability of peptide bonds to form intramolecular hydrogen bonds is important to secondary structure
C. The alpha helix, beta pleated sheet and beta turns are examples of protein secondary structure
D. The steric influence of amino acid residues is important to secondary structure
Question 20
Which of the statements is false about multiple sequence alignment?
A. Both protein and nucleic acid secondary structures can be used
B. More useful in RNA
C. These alignments can be made more accurate by the inclusion of secondary structure information
D. A significant increase in accuracy
Question 21
β-pleated sheets are the examples of _________
A. Primary structure
B. Secondary structure
C. Tertiary structure
D. Quaternary structure