JEE Chemistry Biomolecules MCQs Set B

Question: Proteins are polypeptide of

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question:  Globular proteins are present in

• a) milk
• b) blood
• c) eggs
• d) all of these

Answer: milk

Question: In fibrous proteins, polypeptide chains are held together by

• a) hydrogen bonds
• b) covalent bonds
• c) electrostatic forces of attraction
• d) van der waals forces

Answer: hydrogen bonds

Question: Which of the following is not a function of proteins?

• a) As energy provider for metabolism
• b) As food in the form of meat, eggs
• c) As a biological catalysts in the form of enzymes
• d) Formation of hair, wool, skin and nails

Answer: As energy provider for metabolism

Question: Which of the following is not a fibrous protein?

• a) Insulin
• b) Keratin
• c) Myosin
• d) None of these

Answer: Insulin

Question: A polypeptide with more than hundred amino acid residues, having molecular mass higher than 10,000 u is called

• a) protein
• b) enzyme
• c) hormone
• d) nucleic acid

Answer: protein

Question: An insulin is a ______ which contains _____ amino acids.

• a) protein, 51
• b) hormone, 74
• c) protein, 74
• d) hormone, 51

Answer: protein, 51

Question: Which of the following is an example of globular proteins?

• a) Albumin
• b) Glycine
• c) Alanine
• d) None of these

Answer: Albumin

Question: Which of the following is not a characteristics of fibrous proteins?

• a) These are generally soluble in water
• b) These have elongated shape.
• c) These have fibre like structure.
• d) In the fibrous proteins polypeptide chains are held together by hydrogen and disulphide bonds

Answer: These are generally soluble in water

Question: Which of the following statements is true about a peptide bond (RCONHR)?

• a) It is capable of forming a hydrogen bond
• b) It is non planar
• c) The cis configuration is favoured over the trans configuration.
• d) Single bond rotation is permitted between nitrogen and the carbonyl group

Answer: It is capable of forming a hydrogen bond

Question: Proteins are condensation polymers of

• a)

  

• b)

  

• c)

  

• d) None of these

Answer: 

Question: Primary structure of a protein is

• a)

  

• b) sequence in which amino acids of one polypeptide chain are joined to other chain
• c) the folding patterns of polypeptide chains
• d) the pattern in which the polypeptide chain are arranged

Answer:

Question: The protein that transport oxygen in the blood stream is

• a) haemoglobin
• b) collagen
• c) insulin
• d) albumin

Answer: haemoglobin

Question: The helical structure of protein is stabilized by

• a) hydrogen bonds
• b) peptide bonds
• c) dipeptide bonds
• d) ether bonds

Answer: hydrogen bonds

 More Questions.............................................

Question: Which of the following statements is incorrect?

• a) During denaturation 1° and 2° structures are destroyed but 3° structure remains intact
• b) All the above statements are incorrect.
• c)

  

• d)

  

Answer: During denaturation 1° and 2° structures are destroyed but 3° structure remains intact

Question: Which of the following indicates the order in which amino acids are linked together in a protein ?

• a) Primary structure
• b) Tertiary structure
• c) Secondary structure
• d) Quaternary structure

Answer: Primary structure

Question: Which of the following statement is not true about secondary structure of protein ?

• a) The hydrophilic/ hydrophobic character of amino acid residues is important to secondary structure
• b) The steric influence of amino acid residues is important to secondary structure
• c) The ability of peptide bonds to form intramolecular hydrogen bonds is important to secondary structure
• d) The alpha helix, beta pleated sheet and beta turns are examples of secondary structure of protein

Answer: The hydrophilic/ hydrophobic character of amino acid residues is important to secondary structure

Question: Which of the following terms indicates to the arrangement of different protein subunits in a multiprotein complex ?

• a) quaternary structure
• b) secondary structure
• c) primary structure
• d) tertiary structure

Answer: quaternary structure

Question: Secondary structure of protein is mainly governed by

• a) hydrogen bonds
• b) covalent bonds
• c) disulphide bonds
• d) ionic bonds

Answer: hydrogen bonds

Question: The secondary structure of a protein refers to

• a)

  

• b) fixed configuration of the polypeptide backbone
• c) hydrophobic interactions
• d) None of these

Answer:

Question: Tertiary structure of protein arises due to

• a) folding, coiling and bonding of polypeptide chain
• b) linear sequence of amino acid in polypeptide chain
• c) denatured proteins
• d) folding of polypeptide chain

Answer:  folding, coiling and bonding of polypeptide chain

Question:  Denaturation of proteins leads to loss of its biological activity by

• a) Loss of both secondary and tertiary structures
• b) Loss of both primary and secondary structures
• c) Loss of primary structure
• d) Formation of amino acids

Answer: Loss of both secondary and tertiary structures

Question: Coagulation of protein is known as

• a) denaturing
• b) decay
• c) deamination
• d) dehydration

Answer: denaturing

Question: Which of the following terms refers to the overall three dimensional shape of a protein

• a) Tertiary structure
• b) Primary structure
• c) Secondary structure
• d) Quaternary structure

Answer: Tertiary structure

Question: Which of the following indicates to ‘regions of ordered structure within a protein

• a) Secondary structure
• b) Quaternary structure
• c) Primary structure
• d) Tertiary structure

Answer: Secondary structure

Question: The strongest form of intermolecular bonding that could be formed involving the residue of the amino acid serine is.

• a) hydrogen bond
• b) ionic bond
• c) van der Waals interactions
• d) None of the above

Answer: hydrogen bond

Question: Which of the following protein destroy the antigen when it enters in body cell?

• a) Antibodies
• b) Chromoprotein
• c) Insulin
• d) Phosphoprotein

Answer: Antibodies

Question: Which of the following is incorrect regarding enzymes?

• a) They are very specific for a particular reaction but not for a particular substrate
• b) They are generally named after the compound or class of compounds upon which they work
• c) All the above statements are incorrect
• d) Most of them are globular proteins

Answer: They are very specific for a particular reaction but not for a particular substrate

Question: Enzymes take part in a reaction and

• a) increase the rate of a chemical reaction
• b) decrease the rate of a chemical reaction
• c) both
• d) None of these

Answer: increase the rate of a chemical reaction

Question: Enzymes are made up of

• a) Proteins with specific structure
• b) Edible proteins
• c) Nitrogen containing carbohydrates
• d) Carbohydrates

Answer: Proteins with specific structure

Question: The enzyme which hydrolyses triglycerides to fatty acids and glycerol is called

• a) Lipase
• b) Pepsin
• c) Maltase
• d) Zymase

Answer: Lipase

Question: Which one of the following, statements is incorrect about enzyme catalysis?

• a) Enzymes are least reactive at optimum temperature.
• b) Enzymes are denaturated by ultraviolet rays and at high temperature
• c) Enzyme action is specific
• d) Enzymes are mostly proteinous in nature

Answer: Enzymes are least reactive at optimum temperature.

Question: Insulin production and its action in human body are responsible for the level of diabetes. This compound belongs to which of the following categories?

• a) A hormone
• b) An antibiotic
• c) An enzyme
• d) A co-enzyme

Answer: A hormone

Question: Enzymes are essential as biocatalysts. They function in

• a) aqueous medium, temp = 30–35ºC; pH=7
• b) organic medium
• c) aqueous medium under extreme pH conditions
• d) None of these

Answer: aqueous medium, temp = 30–35ºC; pH=7

Question: Which of the following statements is incorrect?

• a) Enzymes always require a coenzyme in their catalytic  action.
• b) Enzymes action is specific
• c) Enzymes have a very large turnover number
• d) Enzymes are organic catalysts

Answer: Enzymes always require a coenzyme in their catalytic  action.

Question: Among the following vitamins the one whose deficiency causes rickets (bone deficiency) is :

• a) Vitamin D
• b) Vitamin A
• c) Vitamin B
• d) Vitamin C

Answer: Vitamin D

Question: Deficiency of vitamin B₁ causes the disease

• a) Beri-Beri
• b) Sterility
• c) Convulsions
• d) Cheilosis

Answer: Beri-Beri

Question: The vitamin that is not soluble in water is

• a) Vitamin D
• b) Vitamin B₁
• c) Vitamin B₂
• d) Vitamin B₆

Answer: Vitamin D

Question: Anaemia is caused by the deficiency of vitamin

• a) B₁₂
• b) B₁
• c) B₆
• d) B₂

Answer: B₁₂

Question: Vegetable oils like wheat gram oil, sunflower oil etc. are the good source of

• a) vitamin E
• b) vitamin A
• c) vitamin K
• d) vitamin D

Answer: vitamin E

Question: 

Assertion : D(+)– Glucose is dextrorotatory in nature.
Reason : ‘D’ represents its dextrorotatory nature

• a) Assertion is correct, reason is incorrect
• b) Assertion is incorrect, reason is correct
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is correct, reason is incorrect

Question:

Assertion : Sucrose is called an invert sugar.
Reason : On hydrolysis, sucrose bring the change in the sign of rotation from dextro (+) to laevo(–).

• a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
• b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• c) Assertion is correct, reason is incorrect
• d) Assertion is incorrect, reason is correct

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion

Question:

• a) Assertion is incorrect, reason is correct
• b) Assertion is correct, reason is incorrect
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is incorrect, reason is correct

Question:

Assertion : At isoelectric point, the amino group does not migrate under the influence of electric field.
Reason : At isoelectric point, amino acid exists as a zwitterion.

• a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
• b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• c) Assertion is correct, reason is incorrect
• d) Assertion is incorrect, reason is correct

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion

Question:

Assertion : Vitamin D cannot be stored in our body
Reason : Vitamin D is fat soluble vitamin and is excreted from the body in urine.

• a) Assertion is incorrect, reason is correct
• b) Assertion is correct, reason is incorrect
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is incorrect, reason is correct

Question: Which one of the following is the reagent used to identify glucose?

• a) Ammoniacal silver nitrate
• b) Sodium ethoxide
• c) Chloroform and alcoholic KOH
• d) Neutral ferric chloride

Answer: Ammoniacal silver nitrate

Question: Glucose molecule reacts with 'X' number of molecules of phenylhydrazine to yield osazone. The value of 'X' is

• a) three
• b) one
• c) four
• d) two

Answer: three

Question: In the acetylation of glucose, which group is involved in the reaction

• a) alcoholic OH group
• b) CHO group
• c) >C = O group
• d) all of these

Answer: alcoholic OH group

Question: Select the false statement about the cyclic glucose.

• a)

  

• b) Glucose form six-membered ring in which –OH is at C–5 position
• c) If the OH group is added to CHO group it will form cyclic hemiacetal structure
• d) None of these

Answer: 

Question:

• a) specific rotation in beaker I will decrease while in II will increase upto a constant value
• b) the specific rotation of equilibrium mixture in two beakers will be different
• c) the equilibrium mixture in both beakers will be leavorotatory
• d) the equilibrium mixture in both beakers will contain only cyclic form of glucose

Answer: specific rotation in beaker I will decrease while in II will increase upto a constant value

Question: In disaccharides, if the reducing groups of monosaccharides i.e., aldehydic or ketonic groups are bonded, these are nonreducing sugars. Which of the following disaccharide is a non-reducing sugar?

• a)

  

• b)

  

• c) Both
• d) None of these

Answer:

Question: Which of the following pairs represents anomers?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Optical rotation of some compound along with their structures are given below which of them have D configuration.

• a) I, II, III
• b) I, II
• c) II, III
• d) III

Answer: I, II, III

Question:  Structure of a disaccharide formed by glucose and fructose is given below. Identify anomeric carbon atoms in monosaccharide units.

• a) ‘a’ carbon of glucose and ‘b’ carbon of fructose.
• b) ‘f’ carbon of glucose and ‘f’ carbon of fructose
• c) ‘a’ carbon of glucose and ‘e’ carbon of fructose
• d) ‘a’ carbon of glucose and ‘a’ carbon of fructose.

Answer: ‘a’ carbon of glucose and ‘b’ carbon of fructose.

Question: Cyclic structure of fructose resembles with

• a) furan
• b) oxiran
• c) pyridine
• d) pyran

Answer: furan

Question:

• a) D-glucose + D-fructose
• b) D-glucose + L-fructose
• c) L-glucose + L-fructose
• d) L-glucose + D-fructose

Answer: D-glucose + D-fructose

Question: Which one of the following statements is not true regarding (+) Lactose ?

• a) (+) Lactose is a reducing sugar and does not exhibit mutarotation
• b) (+) Lactose, C₁₂H₂₂O₁₁ contains 8-OH groups.
• c) On hydrolysis (+) Lactose gives equal amount of D(+) glucose and D(+) galactose
• d) None of these

Answer: (+) Lactose is a reducing sugar and does not exhibit mutarotation

Question: Which one of the following sets of monosaccharides forms sucrose?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which of the following statements is correct?

• a) Rhamnose having formula C₆H₁₂O₅ is a carbohydrate. Though this is not according to general formula of carbohydrates.
• b) Chemically the carbohydrates may be defined as optically inactive polyhydroxy aldehydes or ketones
• c) Only the compounds following general formula C_x(H₂O)y are carbohydrates
• d) None of these

Answer: Rhamnose having formula C₆H₁₂O₅ is a carbohydrate. Though this is not according to general formula of carbohydrates.

Question: The strongest form of intermolecular bonding that could be formed involving the residue of the amino acid valine is

• a) van der Waals interactions
• b) none of the above
• c) ionic bond
• d) hydrogen bond

Answer: van der Waals interactions