NCERT NEET MCQs Biomolecules

MCQ Type

  1. Lipid are found in acid insoluble fraction during the analysis of chemical composition of tissues. Given the reason
    a) It has very high molecular weight
    b) It is polymer
    c) It has low molecular weight
    d) On grinding, the bio membranes are broken into pieces and form insoluble vesicles
  2. Choose the element which is negligible in living matter
    a) Si b) Mg c) Ca d) S
  3. Name the plant pigments present in the following
    I. Carrots
    II. Tomatoes
    a) I-Tycopene II-Carotene b) I-Carotene II-Lycopene
    c) I-Leucopene II-Carotene d) None of the above
  4. Which one of the following structural formulae of two organic compounds is correctly identified
    along with its related function? a) A- Triglyceride major-Source of energy
    b) B- Uracil -A component of DNA
    c) A-Lecithin -A component of cell membrane
    d) B-Adenine -A nucleotide that makes up nucleic acids

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  1. Silk consists of
    a) Central core of sericin b) Central core of fibroin
    c) Both (a) and (b) d) A fine mixture of fibroin and sericin
  2. Which statement regarding coenzyme is incorrect?
    a) Every coenzyme is a cofactor and every cofactor is a coenzyme
    b) Every coenzyme is a cofactor but every cofactor is not a coenzyme
    c) Most of the coenzymes are nucleotides and are composed of vitamins
    d) Coenzymes are the active constituents of enzymes
  3. The rate of the reaction doubles or decreases by half, for every… °C change in either direction
    a) 10° b) 15° c) 20° d) 27°
  4. Enzyme often have additional parts in their structures that are made up of molecules other than
    proteins. When this additional chemical part is an organic molecule, it is called
    a) Cofactor b) Coenzyme c) Substrate d) Both (a) and (b)
  5. Which one is amino acid?
    a) Pepsin b) Proline c) Cysteine d) Rennin
  6. The sum total composition of acid soluble and acid insoluble fraction pool represents the
    a) Molecular b) Dead cells c) Gene library d) Cellular pool
  7. The ‘lock’ and ‘key’ model of enzyme action illustrates that a particular enzyme molecule
    a) May be destroyed and re synthesised several times
    b) Interacts with a specific type of substrate molecule
    c) Reacts at identical rates under all conditions
    d) Forms a permanent enzyme-substrate complex
  8. Acidic amino acids carry two −COOH and one −NH2 groups per molecule. Keeping this in mind, select the
    correct pair of acidic amino acid
    a) Lysine and arginine b) Aspartic acid and glutamic acid
    c) Glycine and alanine d) Both (a) and (b)
  9. After doing the chemical analysis of organic compounds found in living organisms, two fractions were
    observed namely
    a) Acid soluble pool and acid insoluble pool
    b) Carbon pool and hydrogen pool
    c) Inorganic pool and organic pool
    d) Aqueous pool and non-aqueous pool
  10. Which one is not an example for hydrolases?
    a) Dehydrogenase b) Protease c) Amylase d) Esterase
  11. Which type of protein is present in human skin?
    a) Primary proteins b) Secondary proteins
    c) Tertiary proteins d) Quaternary proteins
  12. The metabolic flow is called
    a) Dynamic state of body constituents
    b) Flow of traffic junctions
    c) Turn over flow
    d) Adiabatic flow of reactions
  13. Read the two reaction A and B given below and select the correct option accordingly
    A. ADP + Pi → ATP
    B. ATP → ADP + Pi
    a) A-Endergonic; B-Exergonic
    b) A-Exergonic; B-Endergonic
    c) A-Endergonic; B-Endergonic

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d) A-Exergonic; B-Exergonic

  1. The pyrimidine base, which confers additional stability to DNA over RNA, is
    a) Adenine b) Guanine c) Cytosine d) Thymine
  2. If the total amount of adenine and thymine in a double-stranded DNA is 60%, then the amount of
    guanine in this DNA will be
    a) 15% b) 20% c) 30% d) 40%
  3. An enzyme extract when subjected to electric field, separates into two fractions each catalyzing
    the same reaction. These fractions are
    a) Allosteric enzymes b) Isoenzymes c) Inducible enzymes d) Coenzymes
  4. Amino acids the substituted methanes. Name the four substituent groups occupying the four valency
    positions
    a) Hydrogen, carboxyl group, amino group and a
    variable group (R)
    b) Two carboxyl groups amino group and OH
    c) Two hydrogen, one carboxyl group, amino group
    and a variable group (R)
    d) Two amino groups, one hydrogen and one
    carboxyl group
  5. The ‘lock’ and ‘key’ theory of enzyme structure and function was proposed by
    a) Morgan b) Robertson c) Brown d) Fischer
  6. Histone octamer contains
    a) Eight types of histones b) Eight histones of four different types
    c) Five histones d) Six types of histones
  7. What is grape sugar?
    a) Glucose b) Fructose c) Sucrose d) Galactose
  8. Pepsin is an ……enzyme
    a) Intracellular b) Extracellular c) Both (a) and (b) d) None of these
  9. Which one is a polymer?
    a) Sucrose b) Glycogen c) Fructose d) Lactose
  10. Which of the following statements are correct?
    I. Acetic acid can form cholesterol
    II. Flow of metabolites through metabolic pathway has a definite rate and direction. It is called dynamic
    state of body constituents
    III. Anabolic pathway is endergonic while catabolic pathway is exergonic
    IV. All biomolecules have a term over, 𝑖.𝑒., they are constantly being changed into some other
    biomolecules and also made from other biomolecules
    The correct options is
    a) All are correct b) I and II are correct
    c) Only IV is correct d) All are wrong
  11. An α-helix is the example of …… protein structure
    a) Primary b) Secondary c) Tertiary d) Quaternary
  12. Which is a reducing sugar?
    a) Galactose b) Gluconic acid
    c) β- methyl galactoside d) Sucrose
  13. Formation of glycogen from glucose is called
    a) Glycogenolysis b) Glycogenesis c) Glycolysis d) Gluconeogenesis
  14. Which of the following statements are correct for polysaccharides?
    I. The polysaccharides are found as a part of the acid insoluble pellet
    II. These are long chains of sugars
    III. They are threads containing different monosaccharides as building blocks
    IV. Cellulose is a polymeric polysaccharide consisting of only one type of monosaccharide 𝑖.𝑒., fructose

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a) All are correct b) All are correct except IV
c) III and IV d) Only IV is correct

  1. Select the false statement
    I. Living process is a constant effort to promote falling into equilibrium
    II. Energy can enter and leave a cell
    III. Matter can enter and leave a cell
    IV. Metabolic pathways are interlinked
    a) Only I b) Only IV c) I and IV d) Only II
  2. Arachidonic acid is
    a) Non-essential fatty acid b) Essential fatty acid
    c) Polyunsaturated fatty acid d) Both (b) and (c)
  3. Inulin is a polymer of
    a) Glucose b) Galactose c) Fructose d) Arabinose
  4. Table sugar consists of
    a) Lactose b) Sucrose c) Maltose d) glucose
  5. For nucleic acids, the building block is a
    a) Nucleotide b) Nucleoside c) Polynucleotide d) Sugar
  6. An example of feedback inhibition is
    a) Cyanide action on cytochrome
    b) Sulpha drug on folic acid synthesizer bacteria
    c) Allosteric inhibition of hexokinase by glucose 6-phosphate
    d) Reaction between succinic dehydrogenase and succinate
  7. The term metabolism means
    a) The sum of all the enzymatically catalysed chemical reactions constantly taking place in the cells and
    tissues of the living organisms
    b) Processes that change the small molecules into larger ones
    c) Processes that converts the large molecules into smaller ones
    d) None of the above
  8. Chitin is a
    a) Polysaccharide b) Nitrogenous polysaccharide
    c) Lipoprotein d) protein
  9. Richest energy compound is
    a) Creatine phosphate b) Protein c) Carbohydrate d) fat
  10. Select the wrong statement.
    a) The building blocks of lipids are amino acids
    b) Majority of enzymes contain a non-protein part called the prosthetic group
    c) The thylakoids are arranged one above the other like a stack of coins forming a granum
    d) Crossing over occurs at pachytene stage of meiosis-I
  11. Which of the following is an essential amino acids?
    a) Valine b) Leucine c) Tryptophan d) All of these
  12. The aggregation of the various kinds of biomolecules in a cell is referred to as the
    a) Acid soluble pool b) Acid insoluble pool
    c) Cellular pool d) None of the above
  13. Secondary metabolites can be observed in
    a) Plant cells b) Fungal cells c) Microbial cells d) All of these
  14. Select the secondary metabolites from the list given below
    I. alkaloids
    II. flavonoids

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III. rubber
IV. essential oils
V. antibiotics
VI. coloured pigments
VII. scents
VIII. gums
IX. spices
Choose the correct option
a) I to IX b) All except II and IX c) I, III, IV and VI d) All except I and VII

  1. What is the starting point in the production of food?
    a) Catabolism b) Metabolism c) Anabolism d) Photosynthesis
  2. Name the amino acids 𝐴−𝐶 correctly a) A-Glycine, B-Serine, C-Alanine b) A-Alanine, B-Glycine, C-Serine
    c) A-Serine, B-Glycine, C-Alanine d) A-Serine, B-Alanine, C-Glycine
  3. Name the heterocyclic compounds which are known as nitrogenous bases
    Choose the most appropriate options
    a) Adenine, guanine, uracil, cytosine and thymine
    b) Adenine, guanine, uracil and thymine
    c) Adenine, guanine, cytosine, uracil
    d) None of these
  4. In which one of the following enzymes copper is necessarily associated as an activator?
    a) Carbonic anhydrase b) Tryptophanase
    c) Lactic dehydrogenase d) Tyrosinase
  5. Identify the structural formulae and select the correct option a) A-Adenine, B-Adenosine, C-Adenylic acid b) A-Guanine, B-Adenosine, C-Adenylic acid
    c) A-Adenosine, B-Adenylic acid, C-Adenine d) A-Uracil, B-Adenosine, C-Adenylic acid
  6. The regulation of the chemical composition of blood and body fluids and other aspects of its internal
    environment by an organism to maintain the physiological process is called
    a) Entropy b) Enthalpy c) Homeostasis d) Metabolism
  7. Name the term given to the left and right ends of a polysaccharide

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a) Left end−N−terminal end, Right
end−C−terminal end b) Left end−reducing end, Right end−non-reducing
end
c) Left end− non-reducing end, Right end−reducing
end d) Left end−C−terminal end, Right
end−N−terminal end

  1. ‘G’ in DNA strand base pairs with ‘C’ by 3… bonds
    a) Hydrogen b) Von der Waal c) Covalent d) Ionic
  2. The inhibitor which inhibits the enzyme activity by binding to the active site of the enzyme, due to the
    close resemblance to the substrate in its molecular structure is called
    a) Non-competitive inhibitor b) Competitive inhibitor
    c) Allosteric modulator d) Feedback inhibitor
  3. Select the correct pair of substituted purines
    a) Cytosine and thymine b) Adenine and guanine
    c) Uracil and cytosine d) Guanine and uracil
  4. Which one of the following is wrongly matched?
    a) Fungi – Chitin b) Phospholipid – Plasma membrane
    c) Enzyme – Lipopolysaccharide d) ATP – Nucleotide derivative
  5. Amino acids are organic compounds and are called α-amino acids. Why?
    a) Amino acids are organic compounds containing an amino group and acidic group as substituents n two
    different carbons
    b) Amino acids are organic compounds containing an amino group and an acidic group as substituents on
    the same carbon
    c) Amino acids are inorganic compounds containing an amino group and acidic group as substituents on
    two different carbons
    d) Amino acids are inorganic compounds containing an amino group and acidic group as substituents on
    the same carbon
  6. Enzymes that catalyze inter-conversion of optical, geometrical or positional isomers, are
    a) Ligases b) Lyases c) Hydrolases d) Isomerases
  7. All the carbon compounds obtained from living tissues are named as
    a) Biomolecules b) Inorganic compounds
    c) Organic compounds d) Only DNA
  8. A fatty acid has a carboxyl group attached to 𝑅 group. The R group could be a
    a) Methyl b) Ethyl
    c) Higher number of −CH2 groups (1 to 19 carbons) d) All of the above
  9. With reference to enzymes, which one of following statements is true?
    a) Apoenzyme=Holoenzyme+Coenzyme b) Holoenzyme=Apoenzyme+Coenzyme
    c) Coenzyme=Apoenzyme+Holoenzyme d) Holoenzyme=Coenzyme+Apoenzyme
  10. Benedict’s reagent test is conducted to confirm the presence of
    a) Polysaccharides like starch b) Lipids
    c) Reducing sugars d) proteins
  11. When a metabolic disequilibrium is in effect, then only cells continue to function
    How do cells avoid reaching metabolic equilibrium?
    a) Use feedback inhibition to turn off pathways
    b) The products of one reaction become the reactant of another reaction and are unable to accumulate
    c) Cellular metabolism utilises only those reactions that are irreversible
    d) Providing constant supply of enzymes
  12. Which of the following radioisotope is not suitable for DNA labeling based studies?
    a) H3 b) P32 c) N15 d) S35
  13. Jacob and Monod named some enzymes as allosteric, whose activity is regulated by

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a) End product b) Substrate c) A by-product d) Coenzyme

  1. Identify the term ‘ash’ in term of living tissue sample analysis from the statements given below

a) Organic compounds oxidised to gaseous form
(CO2 and water vapour) after burning of the tissue
b) The material left after burning the tissue which
contains inorganic elements (e.g., calcium,
magnesium etc.)
c) Compounds removed in the form of gases d) Compounds which may be soluble in intracellular
fluid

  1. Grinding of a living tissue in trichloroacetic acid shows the presence of the inorganic compounds like
    sulphate, phosphate etc, which are categorised in
    a) Acid insoluble fraction
    b) Acid soluble fraction
    c) Both (a) and (b)
    d) Not found in cellular pool
  2. Formation of lactic acid form glucose occurs in… metabolic steps
    a) 25 b) 5 c) 30 d) 10
  3. A nucleotide has three chemically distinct compounds. These are A, B and C
    Choose the correct option for A, B and C
    a) A-Sugar, B-carbonates, C-chlorides
    b) A-DNA, B-cellulose, C-chitin
    c) A-Heterocyclic compound, B-Monosaccharide, C-a phosphate
    d) A-Phosphoric acid, B-Proteins, C-acids
  4. Answer briefly
    I. Hydrolysis of glycogen to glucose is termed as?
    II. Name the enzyme which takes part in the hydrolysis of glycogen
    III. Amylum is an another name of
    IV. Name the polysaccharide formed as the end product of the photosynthesis
    Correct option with all the answers is
    a) I-Glycogenolysis, II-Amylases, III-Starch, IV-Starch b) I-Starch, II-Amylases, III-Glycogenolysis, IV-Starch
    c) I-Starch, II-Glycogenolysis, III-Starch, IV-Amylases d) I-Amylases, II-Glycogenolysis, III-Starch, IV-Starch
  5. Which of the following is not a conjugated protein?
    a) Peptone b) Phosphoprotein c) Lipoprotein d) Chromoprotein
  6. …….. is the most abundant protein in whole of the biosphere
    a) Collagen b) Trypsin c) Insulin d) RUBISCO
  7. Choose the correct option representing X and Y in the given graph a) X-Activation energy without enzymes, Y
    Activation energy with enzyme
    b) X- Activation energy with enzyme, Y-Activation
    energy without enzyme
    c) X-Substrate concentration with enzyme, Y
    Substrate concentration without enzyme
    d) X-Substrate concentration without enzyme, Y
    Substrate concentration with enzyme
  8. Given below is the chemical formula of
    O
    ||

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CH3(CH2)14−C−OH
a) Palmitic acid b) Stearic acid c) Glycerol d) Galactose

  1. Which enzyme is useful as colour brightening agent in detergent industry?
    a) Amylase b) Lipase c) Protease d) Cellulase
  2. Locations or sites in the human DNA where single base DNA differences occur, are called
    a) Repetitive DNA b) VNTR
    c) SNP d) SSCP
  3. An organic substance bound to an enzyme and essential for its activity, is called
    a) Coenzyme b) Holoenzyme c) Apoenzyme d) Isoenzyme
  4. Choose the correct statements
    I. Bond energy (ATP) is utilised for biosynthesis, osmotic and mechanical work that we perform
    II. When glucose is degraded into lactic acid in our muscles, energy of liberated
    III. Assembly of a proteins from amino acids requires energy
    IV. Majority of metabolic reactions can occur in isolation
    V. There are many examples of uncatalysed metabolic reactions
    a) Except IV and V b) I and III c) All of these d) None of these
  5. Maltose consists of which one of the following?
    a) β−glucose and α−galactose b) α−glucose and α−fructose
    c) α−sucrose and β−glucose d) Glucose and glucose
  6. Mannitol is
    a) Amino acid b) Amino alcohol c) Sugar alcohol d) Sugar acid
  7. Almost all enzymes are … in nature
    a) Lipids b) Proteins c) Carbohydrates d) Nucleic Acid
  8. One of the secondary structures exhibited by DNA is…..
    a) Stehenson’s model b) Watson-Crick model c) Bohr’s model d) Wilkenson model
  9. Feedback inhibition of enzymes is affected by which of the following?
    a) Enzyme b) Substrate
    c) End products d) Intermediate end products
  10. All the chemical reactions occurring in living organisms are called
    a) Metabolism b) Anabolism c) Catabolism d) Enzymatic
  11. Given below are two statements A and B. Choose the correct answer related to the statements.
    Statement A Amino acids are amphoteric in their function.
    Statement B All amino acids are necessary for our body.
    a) Statement A is correct but statement B is
    wrong
    b) Both the statements A and B are correct
    c) Statement A is wrong but statement B is
    correct
    d) Both the statements A and B are wrong
  12. The tertiary structure of the proteins containing amino acid cysteine is achieved through
    a) Hydrogen bonds b) Disulphide bonds
    c) Van der Waal’s force d) Ionic bonds
  13. Maltose gives rise to two molecules of
    a) Fructose b) Lactose c) Glucose d) Sucrose
  14. One of the following is a simple protein.
    a) Nucleoprotein b) Glycoprotein c) Lipoprotein d) Albumin
  15. Identify X and Y in the given protein structure

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a) X-N-terminal amino acid, Y-C-terminal amino acid
b) X-N-terminal amino acid, Y-N-terminal amino acid
c) X-C-terminal amino acid, Y-N-terminal amino acid
d) X-C-terminal amino acid, Y-C-terminal amino acid

  1. Which of the following statements are correct?
    I. Relative abundance of carbon and hydrogen with respect to other elements is higher in any living
    organisms
    II. Living organisms have more nitrogen and oxygen per unit mass than inanimate objects (𝑒.𝑔., earth
    crust)
    III. All the elements present in a sample of earth’s crust are also present in a sample of living tissue
    IV. Living organisms have more Ca,Mg,Na in them than inanimate object
    a) All of these b) All except IV c) Only IV d) None of these
  2. Which one is diaminodicarboxylic amino acid?
    a) Cystine b) Lysine c) Cysteine d) Aspartic acid
  3. Which of the following statements about enzymes are correct?
    I. Enzymes do not alter the overall change in free energy for a reaction
    II. Enzymes are highly specific for reactions
    III. The energy input needed to start a chemical reaction is called activation energy
    IV. Enzymes are proteins whose three dimensional shape is key to their functions
    a) I and V b) I, II and V c) II and V d) All of these
  4. Which amino acid is denoted by symbol ‘F’?
    a) Phenylalanine b) Proline
    c) Tryptophan d) Methionine
  5. Which enzyme catalyse the break down of hydrogen peroxide to water and oxygen?
    a) A carbonic anhydrase and catalase b) Hydrolyase and oxidase
    c) Peroxidase and catalase d) Hydrolase and oxidase
  6. Sugar and amino acids are
    a) Primary metabolites b) Secondary metabolites
    c) Feedback d) Inoculum
  7. Which of the following statements regarding enzyme inhibition is correct?
    a) Non-competitive inhibition of an enzyme can be overcome by adding large amount of substrate
    b) Competitive inhibition is seen when a substrate competes with an enzyme for binding to an
    inhibition protein
    c) Competitive inhibition is seen when the substrate and the inhibitor compete
    d) Non-competitive inhibitors often bind to the enzyme irreversibly
  8. Enzymes are functional at
    a) 10-15℃ b) 15-25℃ c) 25-30℃ d) 30-50℃
  9. Cellulose is made up of
    a) Branched chain of glucose molecule linked by α−1, 4 glycosidic bond in straight chain and β−
    1, 6 glycosidic bond at the site of branching
    b) Branched chain of glucose molecule linked by α−1, 6 glycosidic bond in straight chain and β-1,
    4 glycosidic bond at the site of branching
    c) Unbranched chain of glucose molecule linked by β-1, 4 glycosidic bond
    d) Unbranched chain of glucose molecule linked by α-1, 6 glycosidic bond

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