1. The repeating units of proteins are
a) glucose units b) amino acids c) fatty acids d) peptides
2. Amino acids are joined by
a) peptide bond b) hydrogen bond c) ionic bond d) glycosidic bond
3. 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
4. Peptide bond is
a) rigid with partial double bond character b) planar, covalent c) covalent d) all of the above
5. Enzymes are
a) proteins b) carbohydrates c) nucleic acids d) DNA molecule
6. The first protein sequenced by Frederick Sanger is
a) Haemoglobin b) myoglobin c) insulin d) myosin
7. 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
8. The most common secondary structure is
a) α-helix b) β-pleated sheet c) β-pleated sheet parallel d) β-pleated sheet non parallel
9. Myoglobin is a
a) protein with primary structure b) protein with secondary structure c) protein with tertiary structure d) protein with quaternery structure
10. Fibrous protein such as silk fibroin consists of polypeptide chains arranged in
a) α-helix b) β-pleated sheet c) β-helix d) none of these
11. α-helix has
a) 3.4 amino acid residues/turn b) 3.6 amino acid residues/turn c) 3.8 amino acid residues/turn d) 3.0 amino acid residues/turn
12. Tertiary structure is maintained by
a) peptide bond b) hydrogen bond c) di-sulphide bond d) all of the above
13. Haemoglobin has
a) primary structure b) secondary structure c) tertiary structure d) quaternery structure
14. Disulphide bonds are formed between
a) cysteine residues that are close together b) cystine residues that are close together c) proline residues that are close together d) histidine residues that are close together
15. The 3-D structure of protein can be determined by
a) Nuclear magnetic resonance b) X-ray crystallography c) both a and b d) Spectroscopy
Answers 1-b 2-a 3-a 4-d 5-a 6-c 7-a 8-a 9-c 10-b 11-b 12-d 13-d 14-a 15-c
Biology Multiple Choice Quizzes QuizBiology.com
1. The primary structure is primarily maintained by
Peptide bond
Hydrogen bond
Ionic bond
Hydrophobic bonds
2. Which of the following statements are true regarding primary structure of proteins
Primary structure denote the number of amino acids in a protein
Primary structure denote the sequence of amino acids in a protein
Primary structure determines the biological activity of a protein
all of these
3. Which of the following amino acid is a alpha helix terminator
cysteine
alanine
proline
isoleucine
4. The secondary structure is primarily maintained by
Van der waals force
Hydrogen bond
Ionic bond
Hydrophobic bonds
5. Which of the following is the most common and stable conformation for a polypeptide chain
Alpha helix
Beta pleated sheets
Anti parallel beta pleated sheet
Tertiary structure
6. The amyloid protein deposition associated with Alzheimer’s disease is composed of
Alpha helix
Beta pleated sheets
Beta bends
Tertiary structure
7. In alpha helix, the bonding is between the
Adjacent amino acids
Carbonyl oxygen of one peptide bond to the NH group of the 4th amino acid away
Carbonyl oxygen of second peptide bond to the NH group of the 3rd amino acid away
Carbonyl oxygen of second peptide bond to the NH group of the 5th amino acid away
8. Which of the following statements are true regarding tertiary structure of proteins
3 dimensional structure of a protein
It is the biologically active conformation
Primary structure of protein determines the tertiary structure
All of these
9. The most common amino acid in beta bend is
cysteine
glycine
serine
methionine
10. Which of the following statements are true regarding quaternary structure of proteins
Refers to organisation and spatial arrangements of amino acids within a polypeptide chain
Refers to organisation and spatial arrangements of proteins with many polypeptide chains
Both a and b
None of these
MCQ on Biochemistry - Amino acids
1. Amino acids are
a) building blocks of carbohydrates b) building blocks of nucleic acids c) building blocks of lipids d) building blocks of proteins
2. 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
3. The simplest amino acid is
a) Proline b) methionine c) glycine d) serine
4. Which of the following amino acid is
a ‘α-helix terminator’ a) tryptophan b) phenyl alnine c) tyrosine d) proline
5. The first amino acid in a polypeptide chain is
a) Serine b) Valine c) Alanine d) Methionine
6. Which of the following amino acid has buffering capacity
a) Tryptophan b) cysteine c) histidine d) arginine
7. Which of the following is an α imino acid
a) serene b) threonine c) valine d) proline
8. 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
9. Sulphur containing amino acids are
a) Cysteine and methionine b) Methionine and threonine c) Cysteine and threonine d) Cysteine and serine
10. Aromatic amino acids include
a) Phenylalanine, tyrosine and tryptophan b) Phenylalanine, serine and tryptophan c) Threonine, tyrosine and tryptophan d) Asparagine, tyrosine and tryptophan
11. Positively charged basic amino acids are
a) Lysine and arginine b) Lysine and asparagine c) Glutamine and arginine d) Lysine and glutamine
12. Acidic amino acids include
a) Arginine and glutamate b) Aspartate and asparagine c) Aspartate and lysine d) Aspartate and glutamate
13. Amino acids with hydroxyl groups are
a) serine and alanine b) Alanine and valine c) serine and threonine d) Valine and isoleucine
14. The 21st amino acid is
a) hydroxy lysine b) hydroxyl proline c) selenocysteine d) citrulline
15. Absorbance at 280nm exhibited by protein is due to
a) aliphatic amino acids b) all amino acids c) Non-polar amino acids d) aromatic amino acids Online Practice test on
Answers 1-d 2-a 3-c 4-d 5-d 6-c 7-d 8-a 9-a 10-a 11-a 12-d 13-c 14-c 15-d
Multiple Choice Questions- Amino acid and protein chemistry
1-A mutation has changed an isoleucine residue of a protein to Glutamic acid, which
statement best describes its location in a hydrophilic exteriora)
On the surface since it is hydrophilic in nature
b) In side the core of the protein since it is hydrophobic in nature
c) Any where inside or outside
d) Inside the core of protein since it has a polar but uncharged side chain
2- Glycine and proline are the most abundant amino acids in the structure ofa)
Hemoglobin
b) Myoglobin
c) Insulin
d) Collagen
3- Some proteins contain additional amino acids that arise by modification of an amino
acid already present in a peptide, examples includea)
4 -hydroxy proline
b) 5- hydroxy Lysine
c) Gamma Amino Butyric Acid
d) All of the above
4- Choose the incorrect statement out of the followingsa)
Only L amino acids are found in the biological system
b) Glycine is optical inactive
c) Tyrosine is a modified amino acid
d) Seleno cysteine is 21 st amino acid
5- Choose a nano peptide out of the followingsa)
Oxytocin
b) Vasopressin
c) Bradykinin
d) All of the above
6- Which out of the following amino acids carries a net positive charge at the physiological
p H ?
a) Valine
b) Leucine
c) Isoleucine
d) None of the followings
7- Which out of the following amino acids is a precursor for a mediator of allergies and
inflammation?
a) Histidine
b) Tyrosine
c) Phenyl Alanine
d) Tryptophan
8- Mother of a mal nourished child has been instructed to include a complete protein in diet
for her child, which out of the followings proteins should be recommended?
a) Pulses
b) Wheat
c) Soy Protein
d) Milk
9- All of the below mentioned amino acids can participate in hydrogen bonding except one
a) Serine
b) Cysteine
c) Threonine
d) Valine
10- All of the following amino acids are both glucogenic as well as ketogenic except
a) Isoleucine
b) Leucine
c) Tyrosine
d) Phenyl alanine
11- Which out of the following amino acid is a precursor of niacin (Vitamin)?
a) Tyrosine
b) Threonine
c) Tryptophan
d) Phenylalanine
12- The greatest buffering capacity at physiological p H would be provided by a protein
rich in which of the following amino acids?
a) Serine
b) Cysteine
c) Alanine
d) Histidine
13- Which of the following peptides is cyclic in nature-?
a) Glutathione
b) Gramicidin
c) Met encephalin
d) Leuencephalin
14- Which out of the followings is not a fibrous protein?
a)Carbonic anhydrase
b) Collagen
c) Fibrinogen
d ) Keratin
15) -Which of the following amino acid is a limiting amino acid in pulses?
a) Leucine
b) Lysine
c) Methionine
d) Glutamine
16)- Which out of the following is not a haemo protein ?
a) Catalase
b) Myeloperoxidase
c) Glutathione peroxidase
d) Aconitase
17- All the below mentioned proteins are metalloproteins excepta)
Carbonic anhydrase
b) Xanthine oxidase
c) Lactate dehydrogenase
d) Superoxide dismutase
18- Which out of the following is a peptide antibiotic?
a)Erythromycin
b) Gramicidin
c) Ciprofloxacin
d) Tetracycline
19- Choose the Anticancer peptide out of the followingsa)
Bleomycin
b) Methotrexate
c) Cytosine Arabinoside
d) Dideoxy Inosine
20- Which of the following amino acids is most compatible with an α- helical structure?
a)Tryptophan
b) Alanine
c) Leucine
d) Proline
21- The highest concentration of cystine can be found ina)
Melanin
b) Keratin
c) Collagen
d) Myosin
22- In scurvy, which amino acid that is normally part of collagen is not synthesized?
a)Hydroxy Tryptophan
b)Hydroxy Tyrosine
c) Hydroxy Alanine
d) Hydroxy Proline
23- A child with tall stature, loose joints, and detached retinas is found to have a mutation
in collagen. Which of the following amino acids is the recurring amino acid most likely to
be altered in mutations that distort collagen molecules?
a)Glycine
b) Tyrosine
c) Tryptophan
d) Tyrosine
24- Which one of the following amino acids may be considered a hydrophobic amino acid
at physiological p H of 7.4?
a)Isoleucine
b) Arginine
c) Aspartic acid
d) Threonine
25- Which of the characteristics below apply to amino acid Glycine?
a) Optically inactive
b) Hydrophilic, basic and charged
c) Hydrophobic
d) Hydrophilic, acidic and charged
26- Which of the following amino acids in myoglobin, a globular protein, is highly likely to
be localized within the interior of the molecule?
a)Arginine
b) Valine
c) Aspartic acid
d) Lysine
27- Which of the amino acids below is the uncharged derivative of an acidic amino acid?
a)Cystine
b) Tyrosine
c) Glutamine
d) Serine
28-Choose the correct category for milk protein casein out of the followings
a)Nucleoprotein
b) Phospho protein
c) Lipoprotein
d) Glycoprotein
Answers-
1- a
2- d
3- d
4- c
5- d
6- d
7- a
8- d
9- d
10- b
11- c
12- d
13- b
14- a
15- c
16- d
17- c
18- b
19- a
20- b
21- b
22- d
23- a
24- a
25- a
26- b
27- c
28- b
a) glucose units b) amino acids c) fatty acids d) peptides
2. Amino acids are joined by
a) peptide bond b) hydrogen bond c) ionic bond d) glycosidic bond
3. 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
4. Peptide bond is
a) rigid with partial double bond character b) planar, covalent c) covalent d) all of the above
5. Enzymes are
a) proteins b) carbohydrates c) nucleic acids d) DNA molecule
6. The first protein sequenced by Frederick Sanger is
a) Haemoglobin b) myoglobin c) insulin d) myosin
7. 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
8. The most common secondary structure is
a) α-helix b) β-pleated sheet c) β-pleated sheet parallel d) β-pleated sheet non parallel
9. Myoglobin is a
a) protein with primary structure b) protein with secondary structure c) protein with tertiary structure d) protein with quaternery structure
10. Fibrous protein such as silk fibroin consists of polypeptide chains arranged in
a) α-helix b) β-pleated sheet c) β-helix d) none of these
11. α-helix has
a) 3.4 amino acid residues/turn b) 3.6 amino acid residues/turn c) 3.8 amino acid residues/turn d) 3.0 amino acid residues/turn
12. Tertiary structure is maintained by
a) peptide bond b) hydrogen bond c) di-sulphide bond d) all of the above
13. Haemoglobin has
a) primary structure b) secondary structure c) tertiary structure d) quaternery structure
14. Disulphide bonds are formed between
a) cysteine residues that are close together b) cystine residues that are close together c) proline residues that are close together d) histidine residues that are close together
15. The 3-D structure of protein can be determined by
a) Nuclear magnetic resonance b) X-ray crystallography c) both a and b d) Spectroscopy
Answers 1-b 2-a 3-a 4-d 5-a 6-c 7-a 8-a 9-c 10-b 11-b 12-d 13-d 14-a 15-c
Biology Multiple Choice Quizzes QuizBiology.com
1. The primary structure is primarily maintained by
Peptide bond
Hydrogen bond
Ionic bond
Hydrophobic bonds
2. Which of the following statements are true regarding primary structure of proteins
Primary structure denote the number of amino acids in a protein
Primary structure denote the sequence of amino acids in a protein
Primary structure determines the biological activity of a protein
all of these
3. Which of the following amino acid is a alpha helix terminator
cysteine
alanine
proline
isoleucine
4. The secondary structure is primarily maintained by
Van der waals force
Hydrogen bond
Ionic bond
Hydrophobic bonds
5. Which of the following is the most common and stable conformation for a polypeptide chain
Alpha helix
Beta pleated sheets
Anti parallel beta pleated sheet
Tertiary structure
6. The amyloid protein deposition associated with Alzheimer’s disease is composed of
Alpha helix
Beta pleated sheets
Beta bends
Tertiary structure
7. In alpha helix, the bonding is between the
Adjacent amino acids
Carbonyl oxygen of one peptide bond to the NH group of the 4th amino acid away
Carbonyl oxygen of second peptide bond to the NH group of the 3rd amino acid away
Carbonyl oxygen of second peptide bond to the NH group of the 5th amino acid away
8. Which of the following statements are true regarding tertiary structure of proteins
3 dimensional structure of a protein
It is the biologically active conformation
Primary structure of protein determines the tertiary structure
All of these
9. The most common amino acid in beta bend is
cysteine
glycine
serine
methionine
10. Which of the following statements are true regarding quaternary structure of proteins
Refers to organisation and spatial arrangements of amino acids within a polypeptide chain
Refers to organisation and spatial arrangements of proteins with many polypeptide chains
Both a and b
None of these
MCQ on Biochemistry - Amino acids
1. Amino acids are
a) building blocks of carbohydrates b) building blocks of nucleic acids c) building blocks of lipids d) building blocks of proteins
2. 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
3. The simplest amino acid is
a) Proline b) methionine c) glycine d) serine
4. Which of the following amino acid is
a ‘α-helix terminator’ a) tryptophan b) phenyl alnine c) tyrosine d) proline
5. The first amino acid in a polypeptide chain is
a) Serine b) Valine c) Alanine d) Methionine
6. Which of the following amino acid has buffering capacity
a) Tryptophan b) cysteine c) histidine d) arginine
7. Which of the following is an α imino acid
a) serene b) threonine c) valine d) proline
8. 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
9. Sulphur containing amino acids are
a) Cysteine and methionine b) Methionine and threonine c) Cysteine and threonine d) Cysteine and serine
10. Aromatic amino acids include
a) Phenylalanine, tyrosine and tryptophan b) Phenylalanine, serine and tryptophan c) Threonine, tyrosine and tryptophan d) Asparagine, tyrosine and tryptophan
11. Positively charged basic amino acids are
a) Lysine and arginine b) Lysine and asparagine c) Glutamine and arginine d) Lysine and glutamine
12. Acidic amino acids include
a) Arginine and glutamate b) Aspartate and asparagine c) Aspartate and lysine d) Aspartate and glutamate
13. Amino acids with hydroxyl groups are
a) serine and alanine b) Alanine and valine c) serine and threonine d) Valine and isoleucine
14. The 21st amino acid is
a) hydroxy lysine b) hydroxyl proline c) selenocysteine d) citrulline
15. Absorbance at 280nm exhibited by protein is due to
a) aliphatic amino acids b) all amino acids c) Non-polar amino acids d) aromatic amino acids Online Practice test on
Answers 1-d 2-a 3-c 4-d 5-d 6-c 7-d 8-a 9-a 10-a 11-a 12-d 13-c 14-c 15-d
Multiple Choice Questions- Amino acid and protein chemistry
1-A mutation has changed an isoleucine residue of a protein to Glutamic acid, which
statement best describes its location in a hydrophilic exteriora)
On the surface since it is hydrophilic in nature
b) In side the core of the protein since it is hydrophobic in nature
c) Any where inside or outside
d) Inside the core of protein since it has a polar but uncharged side chain
2- Glycine and proline are the most abundant amino acids in the structure ofa)
Hemoglobin
b) Myoglobin
c) Insulin
d) Collagen
3- Some proteins contain additional amino acids that arise by modification of an amino
acid already present in a peptide, examples includea)
4 -hydroxy proline
b) 5- hydroxy Lysine
c) Gamma Amino Butyric Acid
d) All of the above
4- Choose the incorrect statement out of the followingsa)
Only L amino acids are found in the biological system
b) Glycine is optical inactive
c) Tyrosine is a modified amino acid
d) Seleno cysteine is 21 st amino acid
5- Choose a nano peptide out of the followingsa)
Oxytocin
b) Vasopressin
c) Bradykinin
d) All of the above
6- Which out of the following amino acids carries a net positive charge at the physiological
p H ?
a) Valine
b) Leucine
c) Isoleucine
d) None of the followings
7- Which out of the following amino acids is a precursor for a mediator of allergies and
inflammation?
a) Histidine
b) Tyrosine
c) Phenyl Alanine
d) Tryptophan
8- Mother of a mal nourished child has been instructed to include a complete protein in diet
for her child, which out of the followings proteins should be recommended?
a) Pulses
b) Wheat
c) Soy Protein
d) Milk
9- All of the below mentioned amino acids can participate in hydrogen bonding except one
a) Serine
b) Cysteine
c) Threonine
d) Valine
10- All of the following amino acids are both glucogenic as well as ketogenic except
a) Isoleucine
b) Leucine
c) Tyrosine
d) Phenyl alanine
11- Which out of the following amino acid is a precursor of niacin (Vitamin)?
a) Tyrosine
b) Threonine
c) Tryptophan
d) Phenylalanine
12- The greatest buffering capacity at physiological p H would be provided by a protein
rich in which of the following amino acids?
a) Serine
b) Cysteine
c) Alanine
d) Histidine
13- Which of the following peptides is cyclic in nature-?
a) Glutathione
b) Gramicidin
c) Met encephalin
d) Leuencephalin
14- Which out of the followings is not a fibrous protein?
a)Carbonic anhydrase
b) Collagen
c) Fibrinogen
d ) Keratin
15) -Which of the following amino acid is a limiting amino acid in pulses?
a) Leucine
b) Lysine
c) Methionine
d) Glutamine
16)- Which out of the following is not a haemo protein ?
a) Catalase
b) Myeloperoxidase
c) Glutathione peroxidase
d) Aconitase
17- All the below mentioned proteins are metalloproteins excepta)
Carbonic anhydrase
b) Xanthine oxidase
c) Lactate dehydrogenase
d) Superoxide dismutase
18- Which out of the following is a peptide antibiotic?
a)Erythromycin
b) Gramicidin
c) Ciprofloxacin
d) Tetracycline
19- Choose the Anticancer peptide out of the followingsa)
Bleomycin
b) Methotrexate
c) Cytosine Arabinoside
d) Dideoxy Inosine
20- Which of the following amino acids is most compatible with an α- helical structure?
a)Tryptophan
b) Alanine
c) Leucine
d) Proline
21- The highest concentration of cystine can be found ina)
Melanin
b) Keratin
c) Collagen
d) Myosin
22- In scurvy, which amino acid that is normally part of collagen is not synthesized?
a)Hydroxy Tryptophan
b)Hydroxy Tyrosine
c) Hydroxy Alanine
d) Hydroxy Proline
23- A child with tall stature, loose joints, and detached retinas is found to have a mutation
in collagen. Which of the following amino acids is the recurring amino acid most likely to
be altered in mutations that distort collagen molecules?
a)Glycine
b) Tyrosine
c) Tryptophan
d) Tyrosine
24- Which one of the following amino acids may be considered a hydrophobic amino acid
at physiological p H of 7.4?
a)Isoleucine
b) Arginine
c) Aspartic acid
d) Threonine
25- Which of the characteristics below apply to amino acid Glycine?
a) Optically inactive
b) Hydrophilic, basic and charged
c) Hydrophobic
d) Hydrophilic, acidic and charged
26- Which of the following amino acids in myoglobin, a globular protein, is highly likely to
be localized within the interior of the molecule?
a)Arginine
b) Valine
c) Aspartic acid
d) Lysine
27- Which of the amino acids below is the uncharged derivative of an acidic amino acid?
a)Cystine
b) Tyrosine
c) Glutamine
d) Serine
28-Choose the correct category for milk protein casein out of the followings
a)Nucleoprotein
b) Phospho protein
c) Lipoprotein
d) Glycoprotein
Answers-
1- a
2- d
3- d
4- c
5- d
6- d
7- a
8- d
9- d
10- b
11- c
12- d
13- b
14- a
15- c
16- d
17- c
18- b
19- a
20- b
21- b
22- d
23- a
24- a
25- a
26- b
27- c
28- b