Post on 25-Jun-2020
transcript
MCQs
PROTEINS
Dr. RUCHIKA YADU
Q1. The repeating units of
proteins are
a) glucose units
b) amino acids
c) fatty acids
d) peptides
Q2. Amino acids are joined by
a) peptide bond
b) hydrogen bond
c) ionic bond
d) glycosidic bond
Q3. The primary structure of
protein represents
a) Linear sequence of amino acids joined by
peptide bond
b) 3-dimensional structure of protein
c) helical structure of protein
d) sub unit structure of protein
Q4. Amino acids has
a) both amino group and carboxyl group
b) both amino group and keto group
c) amino group only
d) carboxyl group only
Q5. The simplest amino acid is
a) Proline
b) methionine
c) glycine
d) serine
Q6. The first amino acid in a
polypeptide chain is
a) Serine
b) Valine
c) Alanine
d) Methionine
Q7. Aromatic amino acids
include
a) Phenylalanine, tyrosine and tryptophan
b) Phenylalanine, serine and tryptophan
c) Threonine, tyrosine and tryptophan
d) Asparagine, tyrosine and tryptophan
Q8. Positively charged basic
amino acids are
a) Lysine and arginine
b) Lysine and asparagine
c) Glutamine and arginine
d) Lysine and glutamine
Q9. Acidic amino acids include
a) Arginine and glutamate
b) Aspartate and asparagine
c) Aspartate and lysine
d) Aspartate and glutamate
Q10. All of the following are
essential amino acids except
a) Lysine
b) Aspartate
c) Tryptophan
d) Histidine
Q11. Haemoglobin has
a) primary structure
b) secondary structure
c) tertiary structure
d) quaternary structure
Q12. A dipeptide has
a) 2 amino acids and 1 peptide bond
b) 2 amino acids and 2 peptide bonds
c) 2 amino acids and 3 peptide bonds
d) 2 amino acids and 4 peptide bonds
Q13. Which of the following statements is/are
true regarding primary structure of proteins
a) Primary structure denote the number of amino acids
in a protein
b) Primary structure denote the sequence of amino
acids in a protein
c) Primary structure determines the biological activity
of a protein
d) all of these
Q14. Which of the following statements is true
regarding quaternary structure of proteins
a) Refers to organization and spatial arrangements
of amino acids within a polypeptide chain
b) Refers to organization and spatial arrangements
of proteins with many polypeptide chains
c) Both a and b
d) None of these
Q15.Which type of bonding is responsible
for stabilizing the secondary structure of
proteins?
a) Disulphide bridges between cysteine residues.
b) Hydrogen bonding between the C=O and N-H
groups of peptide bonds.
c) Peptide bonds between amino acids.
d) Salt bridges between charged side chains of
amino acids.
Q16. 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
Q17. 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
Q18. In alpha helix, the bonding is
between the
a) Adjacent amino acids
b) Carbonyl oxygen of one peptide bond to the NH group of the 4th amino acid away
c) Carbonyl oxygen of second peptide bond to the NH group of the 3rd amino acid away
d) Carbonyl oxygen of second peptide bond to the NH group of the 5th amino acid away
Q19. The primary structure is
primarily maintained by
a) Peptide bond
b) Hydrogen bond
c) Ionic bond
d) Hydrophobic bonds
Q20. The secondary structure is
primarily maintained by
a) Van der waals force
b) Hydrogen bond
c) Ionic bond
d) Hydrophobic bonds
Q21. Which of the following is the most
common and stable conformation for a
polypeptide chain
a) Alpha helix
b) Beta pleated sheets
c) Anti parallel beta pleated sheet
d) Tertiary structure
Q22. Amino acids with hydroxyl
groups are
a) serine and alanine
b) Alanine and valine
c) serine and threonine
d) Valine and isoleucine
Q23. The naturally occurring
form of amino acid in proteins
a) L-amino acids only
b) D-amino acids only
c) both L and D amino acids
d) none of these
Q24. Sulphur containing amino
acids are
a) Cysteine and methionine
b) Methionine and threonine
c) Cysteine and threonine
d) Cysteine and serine
Q25. Tertiary structure is
maintained by
a) peptide bond
b) hydrogen bond
c) di-sulphide bond
d) all of the above
Ques. Option Answer
1 b amino acids
2 a peptide bond
3 a Linear sequence of amino acids joined by peptide bond
4 a both amino group and carboxyl group 5 c glycine 6 d Methionine7 a Phenylalanine, tyrosine and tryptophan
8 a Lysine and arginine
9 d Aspartate and glutamate
10 b Aspartate
11 d quaternary structure
12 a 2 amino acids and 1 peptide bond
13 d all of these
14 b Refers to organization and spatialarrangements of proteins with manypolypeptide chains
15 b Hydrogen bonding between the C=O and N-H groups of peptide bonds.
16 b α-helix17 c β-pleated sheets
18 b Carbonyl oxygen of one peptidebond to the NH group of the4th amino acid away
19 d Hydrophobic bonds
20 b Hydrogen bond
21 a Alpha helix
22 c serine and threonine
23 a L-amino acids only
24 a Cysteine and methionine
25 d all of the above