NEET Chemistry Biomolecules MCQs Set B

Question: Which of the following is not a pyrimidine base?

• a) Thymine
• b) Cytosine
• c) Uracil
• d) Guanine

Answer: Guanine

Question: Which of the following is not a fat soluble vitamin?

• a) Vitamin A
• b) Vitamin K
• c) Vitamin E
• d) Vitamin H

Answer: Vitamin H

Question:

A and B are

• a) Pyruvic acid and black mass
• b) Leavulic acid and ethanol
• c) Pyruvic acid and ethanol
• d) Leavulic acid and black mass

Answer: Leavulic acid and black mass

Question:

Amino acid having

• a) Two NH₂ groups 
• b) One –COOH group
• c) Two –COOH groups 
• d) Three – COOH groups 

Answer: Two –COOH groups 

Question: Formation of 1º and secondary structure of proteins involves linkages

• a) Peptide linkage, H-bond
• b) H-Bond, disulphide bond
• c) Disulphide bond, peptide linkage
• d) H-bond, H-bond

Answer: Peptide linkage, H-bond

Question: Which of the following ketone reduces Tollen's reagent in basic medium?

• a) CH₃COCH₃
• b)

  

• c)

  

• d)

  

Answer:

Question:  In the given structure of the carbohydrate, which of the following are used while naming it?

• a) Pentose
• b) Hexo
• c) Aldose
• d) Furano

Answer: Furano

Question: An optically active compound having molecular formula C₆H₁₂O₆ is found in two isomeric forms. When isomers dissolved in water, they show the following equilibria

Such isomers are called

• a) Anomers
• b) Enantiomers
• c) Positional isomers
• d) Geometrical isomers

Answer: Anomers

Question: Which of the following is not used for testing proteins?

• a) Molisch's test
• b) Biuret test
• c) Ninhydrin test
• d) Millon's test

Answer: Molisch's test

Question: Which of the following hormones is produced under the condition of stress which stimulate : glycogenolysis in the liver of human beings ?

• a) Thyroxin
• b) Insulin
• c) Adrenaline
• d) Estradiol

Answer: Adrenaline

Question: D(+) glucose reacts with hydroxyl amine and yield an oxime. The structure of the oxime would be

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:  Deficiency of vitamin B₁ causes the disease 

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

Answer: Beri-Beri

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

• a) β–D–Glucopyranose and α–D–fructofuranose 
• b) α–D–Glucopyranose and β–D–fructopyranose
• c) α–D–Galactopyranose and α–D–Glucopyranose 
• d) α–D–Glucopyranose and β–D– fructofuranose

Answer:  α–D–Glucopyranose and β–D– fructofuranose

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

• a) (+) Lactose, C₁₂H₂₂O₁₁ contains 8-OH groups
• b) On hydrolysis (+) Lactose gives equal amount of D(+) glucose and D(+) galactose
• c) (+) Lactose is a β-glycoside formed by the union of a molecule of D(+) glucose and a molecule of D(+)galactose
• d) (+) Lactose is a reducing sugar and does not exhibit mutarotation

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

Question: Which of the statements about "Denaturation" given below are correct? (a) Denaturation of proteins causes loss of secondary and tertiary structures of the protein. (b) Denaturation leads to the conversion of double strand of DNA into single strand. (c) Denaturation affects primary structure which gets distorted.

• a) (a) & (b)
• b) (a), (b) & (c)
• c) (b) & (c)
• d) (a) & (c)

Answer: (a) & (b)

Question: Which of the following is not a fat soluble vitamin ?

• a) Vitamin E
• b) Vitamin A
• c) Vitamin B complex
• d) Vitamin D

Answer: Vitamin B complex

Question: Which one of the following does not exhibit the phenomemon of mutarotation ?

• a) (+) Sucrose
• b) (+) Lactose
• c) (+) Maltose
• d) (–) Fructose

Answer: (+) Sucrose

Question: Fructose reduces Tollen's reagent due to

• a) Asymmetric carbons
• b) Primary alcoholic group
• c) Secondary alcoholic group
• d) Enolisation of fructose followed by conversion to aldehyde by base

Answer: Enolisation of fructose followed by conversion to aldehyde by base

Question: The segment of DNA which acts as the instrumental manual for the synthesis of the protein is

• a) Ribose
• b) Gene
• c) Nucleoside
• d) Nucleotide

Answer: Gene

Question: Which of the following hormones contains iodine ?

• a) Testosterone
• b) Adrenaline
• c) Thyroxine
• d) Insulin

Answer: Thyroxine

Question: In DNA, the complimentary bases are

• a) Uracil and adenine; cytosine and guanine
• b) Adenine and thymine; guanine and cytosine
• c) Adenine and thymine; guanine and uracil
• d) Adenine and guanine; thymine and cytosine

Answer: Adenine and thymine; guanine and cytosine

Question: Which one of the following is an amine hormone ?

• a) Progesterone
• b) Thyroxine
• c) Oxypurin
• d) Insulin

Answer: Thyroxine

Question: Which one of the following vitamins is water-soluble?

• a) Vitamin A
• b) Vitamin B
• c) Vitamin E
• d) Vitamin K

Answer: Vitamin B

Question: RNA and DNA are chiral molecules, their chirality is due to

• a)  D - sugar component 
• b)  L - sugar component
• c) Chiral bases
• d) Chiral phosphate ester units

Answer:  D - sugar component 

Question:  During the process of digestion, the proteins present in food materials are hydrolysed to amino acids. The two enzymes involved in the process

are respectively 

• a) Amylase and maltase
• b) Diastase and lipase
• c) Pepsin and trypsin
• d) Invertase and zymase

Answer: Pepsin and trypsin

Question: The human body does not produce

• a) DNA
• b) Vitamins
• c) Hormones
• d) Enzymes

Answer: Vitamins

Question: Which one of the following is a peptide hormone ?

• a) Glucagon
• b) Testosterone
• c) Thyroxine
• d) Adrenaline

Answer: Glucagon

Question: The cell membranes are mainly composed of

• a) Carbohydrates
• b) Proteins
• c) Phospholipids
• d) Fats

Answer: Phospholipids

Question: Which functional group participates in disulphide bond formation in proteins ?

• a) Thiolactone
• b) Thiol
• c) Thioether
• d) Thioester

Answer: Thiol

Question: Which is not the correct statement about RNA and DNA?

• a) DNA is active in virus while RNA never appears in virus
• b) DNA exists as dimer while RNA is usually single stranded
• c) DNA contains deoxyribose as its sugar and RNA contains ribose
• d) RNA contains uracil in place of thymine (found in DNA) as a base

Answer: DNA is active in virus while RNA never appears in virus

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

Question: What is the nature of glucose-glucose linkage in starch that makes its so susceptible to acid hydrolysis?

• a) Starch is hemiacetal
• b) Starch is acetal
• c) Starch is polymer
• d) Starch contains only few molecules of glucose

Answer: Starch is acetal

Question:

glucose, equilibrium constant for this is 1.8. The percentage of α-(D) glucose at equilibrium is

• a) 35.7
• b) 55.6
• c) 44.4
• d) 64.3

Answer: 35.7

Question: By the action of enzymes, the rate of biochemical reaction

• a) Does not change
• b) Increases
• c) Decreases
• d) Either (1) or (3)

Answer: Increases

Question: The secondary structure of a protein refers to

• a) Regular folding patterns of contiguous portions of the polypeptide chain
• b) Three-dimensional structure, specially the bond between amino acid residues that are distant from each other in the polypeptide chain
• c) Mainly denatured proteins and structures of prosthetic groups
• d) Linear sequence of amino acid residues in the polypeptide chain

Answer: Regular folding patterns of contiguous portions of the polypeptide chain

Question: The oxidation of glucose is one of the most important reactions in a living cell. What is the number of ATP molecules generated in cells from one molecule of glucose?

• a) 28
• b) 38
• c) 12
• d) 18

Answer: 38

Question: Which of the following statements about enzymes are true?

• a) Enzyme catalyse chemical reactions by lowering the activation energy
• b) Enzymes are highly specific both in binding chiral substrates and in catalysing their reactions
• c) Enzymes lack in nucleophilic groups
• d) Pepsin is proteolytic enzyme

Answer: Enzymes are highly specific both in binding chiral substrates and in catalysing their reactions

Question:  The α–D glucose and β–D glucose differ from each other due to difference in carbon atom with respect to its

• a) Number of OH groups
• b) Size of hemiacetal ring
• c) Conformation
• d) Configuration

Answer: Configuration

Question: Haemoglobin is

• a) A vitamin
• b) A carbohydrate
• c) An enzyme
• d) A globular protein

Answer: A globular protein

Question: The function of enzymes in the living system is to

• a) Catalyse biochemical reactions
• b) Provide energy
• c) Transport oxygen
• d) Provide immunity

Answer: Provide immunity

Question: The number of molecules of ATP produced in the lipid metabolism of a molecule of palmitic acid is

• a) 56
• b) 36
• c) 130
• d) 86

Answer: 56

Question: Glucose molecule reacts with X number of molecules of phenyl-hydrazine to yield osazone. The value of X is

• a) Two
• b) One
• c) Four
• d) Three

Answer: Three

Question: Which of the following is the sweetest sugar?

• a) Fructose
• b) Glucose
• c) Sucrose
• d) Maltose

Answer: Fructose

Question:  α-D-glucose and β-D glucose are

• a) Epimers
• b) Anomer
• c) Enantiomers
• d) Diastereomers

Answer: Anomer

Question: Which one is responsible for production of energy in bio reaction?

• a) Thyroxine
• b) Adrenaline
• c) Oestrogen
• d) Progesterone

Answer: Thyroxine

Question: Mg is present in

• a) Chlorophyll
• b) Haemoglobin
• c) Vitamin-D
• d) Vitamin-B

Answer: Chlorophyll

Question: Which of the following give positive Fehling solution test?

• a) Sucrose
• b) Glucose
• c) Fats
• d) Protein

Answer: Glucose

Question: Which of the following is correct about H-bonding in nucleotide?

• a) A – T G – C 
• b) A – G T – C
• c) G – T A – C
• d) A – A T – T

Answer:  A – T G – C 

Question:

(peptide bond). Which statement is incorrect about peptide bond?

• a)  C – N bond length in proteins is longer than usual bond length of N – C bond
• b)

  Spectroscopic analysis show planar structure of 

• c) C – N bond length in proteins is smaller than usual bond length of C – N bond
• d) None of these

Answer:  C – N bond length in proteins is longer than usual bond length of N – C bond

Question: Enzymes are made up of

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

Answer: Edible proteins

Question: Which is not true statement?

• a) α-carbon of α-amino acid is asymmetric
• b) All amino acids are found in L-form
• c) Human body can synthesize all amino acids they need
• d) At pH = 7 both amino and carboxylic groups exist in ionised form

Answer: Human body can synthesize all amino acids they need

Question:   Vitamin B₁₂ contains

• a) Fe (II)
• b) Co (III) 
• c) Zn (II) 
• d) Ca (II)

Answer:  Co (III) 

Question: Glycolysis is

• a) Oxidation of glucose to glutamate
• b) Conversion of pyruvate to citrate
• c) Oxidation of glucose to pyruvate
• d) Conversion of glucose to haem

Answer: Oxidation of glucose to pyruvate

Question: Which of the following structure represents the peptide chain?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Phospholipids are esters of glycerol with

• a) Three carboxylic acid residues
• b) Two carboxylic acid residues and one phosphate group
• c) One carboxylic acid residue and two phosphate groups
• d) Three phosphate groups

Answer: Two carboxylic acid residues and one phosphate group

Question: A sequence of how many nucleotides in messenger RNA makes a codon for an amino acid?

• a) Three
• b) Four
• c) One
• d) Two

Answer: Three

Question: Chargaff’s rule states that in an organism

• a) Amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C)
• b) Amount of adenine (A) is equal to that of guanine (G) and the amount of thymine (T) is equal to that of cytosine (C)
• c) Amount of adenine (A) is equal to that of cytosine (C) and the amount of thymine (T) is equal to that of guanine (G)
• d) Amounts of all bases are equal

Answer: Amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C)

Question: The hormone that helps in the conversion of glucose to glycogen is

• a) Cortisone
• b) Bile acids
• c) Adrenaline
• d) Insulin

Answer: Insulin

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

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

Answer: Lipase

Question: The correct statement in respect of protein haemoglobin is that it

• a) Functions as a catalyst for biological reactions
• b) Maintains blood sugar level
• c) Acts as an oxygen carrier in the blood
• d) Forms antibodies and offers resistance to diseases

Answer: Acts as an oxygen carrier in the blood

Question:  Number of chiral carbons in β-D-(+) glucose is

• a) Five
• b) Six
• c) Three
• d) Four

Answer: Four