MCQ 511 Mark
$\text{DNA}$ is composed of repeating units of:
- ARibonucleosides.
- BDeoxyribonucleosides.
- CRibonucleotides.
- ✓Deoxyribonucleotides.
Answer
View full question & answer→Correct option: D.
Deoxyribonucleotides.
Deoxyribonucleotides.
Questions · Page 2 of 4
M.C.Q (1 Marks)
MCQ 521 Mark
The $K$ value of an enzyme is the substrate concentration at:
- A$\text{V}_{\text{max}}$
- ✓$\frac{1}{2}\text{V}_{\text{max}}$
- C$\frac{1}{4}\text{V}_\text{max}$
- D$\frac{3}{4}\text{V}_{\text{max}}$
Answer
View full question & answer→Correct option: B.
$\frac{1}{2}\text{V}_{\text{max}}$
$\frac{1}{2}\text{V}_{\text{max}}$
MCQ 531 Mark
Which of the following is an organic compound found in most cells:
- ✓Glucose
- BWater
- CSodium chloride
- DOxygen
Answer
View full question & answer→Correct option: A.
Glucose
Glucose
MCQ 541 Mark
Enzymes that catalyse inter$-$conversion of optical, geometrical or positional isomers are:
- ALigases
- BLyases
- CHydrolases
- ✓Isomerases
Answer
View full question & answer→Correct option: D.
Isomerases
Ligases are the enzymes which catalyze joining together of two $\text{DNA}$ segments.
Lyases catalyze the breaking of chemical bonds without hydrolysis while hydrolases catalyze hydrolytic cleavage of bonds.
Isomerases catalyze interconversion of optical, geometrical or positional isomers of a particular enzyme.
Lyases catalyze the breaking of chemical bonds without hydrolysis while hydrolases catalyze hydrolytic cleavage of bonds.
Isomerases catalyze interconversion of optical, geometrical or positional isomers of a particular enzyme.
MCQ 551 Mark
Which one of the following pair is wrongly matched:
- ADetergents $-$ lipase
- ✓Alcohol $-$ nitrogenase
- CFruit juice $-$ pectinase
- DTextile $-$ amylase
Answer
View full question & answer→Correct option: B.
Alcohol $-$ nitrogenase
This question relates to the industrial applications of enzymes.
Alcohol is not produced by the use of nitrogenase.
Nitrogenase performs complex functions of nitrogen fixation by bacteria.
Alcohol is produced by the fermentation process of sugars carried out by Yeast.
Alcohol is not produced by the use of nitrogenase.
Nitrogenase performs complex functions of nitrogen fixation by bacteria.
Alcohol is produced by the fermentation process of sugars carried out by Yeast.
MCQ 561 Mark
Enzymes, vitamins and hormones are common in:
- AEnhancing oxidative metabolism.
- BBeing synthesised in the body of organisms.
- CBeing proteinaceous.
- ✓Regulating metabolism.
Answer
View full question & answer→Correct option: D.
Regulating metabolism.
Regulating metabolism.
MCQ 571 Mark
Enzymes are absent in:
- AAlgae.
- BFungi.
- CCyanobacteria.
- ✓Viruses.
Answer
View full question & answer→Correct option: D.
Viruses.
Viruses.
MCQ 581 Mark
Which of the following enzyme digests other enzymes:
- ADehydrogenases
- BLipases
- ✓Peptidases
- DAldolases
Answer
View full question & answer→Correct option: C.
Peptidases
Most of the enzymes are proteins.Proteins are biological macromolecules made up of amino acids joined together by peptide bonds.
Peptidases are enzymes, which cleave or break peptide bonds.
The action of peptidase enzymes will cleave or break peptide bonds, thus breaking the primary structure of enzymes or digestion of enzyme.
Peptidases are enzymes, which cleave or break peptide bonds.
The action of peptidase enzymes will cleave or break peptide bonds, thus breaking the primary structure of enzymes or digestion of enzyme.
MCQ 591 Mark
Cleavage of specific covalent bonds and removal of groups without hydrolysis is the property of:
- ✓Lyases.
- BTransferases.
- CIsomerases.
- DHydrolases.
Answer
View full question & answer→Correct option: A.
Lyases.
Lyases.
MCQ 601 Mark
The type of linkage present in carbohydrates is:
- APeptide
- ✓Glycosidic
- CAmide
- DPhosphate bonds
Answer
View full question & answer→Correct option: B.
Glycosidic
Glycosidic bonds are the bonds formed between hemiacetal or hemiketal group of carbohydrates and hydroxyl group of another molecule.
It is a condensation reaction which leads to release of water molecules.
It is a condensation reaction which leads to release of water molecules.
MCQ 611 Mark
In which one of the following groups, all the three are examples of polysaccharides?
- ✓Starch, glycogen, cellulose.
- BSucrose, maltose, glucose.
- CGlucose, fructose, lactose.
- DGalactose, starch, sucrose.
Answer
View full question & answer→Correct option: A.
Starch, glycogen, cellulose.
Starch, glycogen, cellulose.
MCQ 621 Mark
The function of enzymes in the living system is to:
- ATransport oxygen
- BProvide immunity
- ✓Catalyse biochemical reaction
- DProvide energy
Answer
View full question & answer→Correct option: C.
Catalyse biochemical reaction
The function of enzymes in the living system is to catalysed biochemical reactions without involving in the reaction.
It means enzymes speed up the rate of reaction by lowering activation energy, so the reaction proceeds faster and at the end same enzymes can are obtained without any changes in it.
It means enzymes speed up the rate of reaction by lowering activation energy, so the reaction proceeds faster and at the end same enzymes can are obtained without any changes in it.
MCQ 631 Mark
Coenzyme of a conjugate enzyme is more often a/ an:
- ✓Vitamin.
- BInorganic compound.
- CMetal ion.
- DBoth $(b)$ and $(c).$
Answer
View full question & answer→Correct option: A.
Vitamin.
Vitamin.
MCQ 641 Mark
An enzyme brings about.
- ✓Reduction in activation energy.
- BIncrease in activation energy.
- CIncrease in reaction time.
- DDecrease in reaction time.
Answer
View full question & answer→Correct option: A.
Reduction in activation energy.
Reduction in activation energy.
MCQ 651 Mark
Aminoacids, have both an amino group and a carboxyl group in their structure. Which one of the following is an amino acid?
- AFormic acid.
- BGlycerol.
- CGlycolic Acid.
- ✓Glycine.
Answer
View full question & answer→Correct option: D.
Glycine.
Glycine is the simplest amino acid with hydrogen as $R$ group. Formic acid is simplest carboxylic acid molecule. It is chemically $\text{HCOOH.}$ Glycerol is a polyol compound, which is chemically propane$-1, 2, 3-$triol and glycolic acid is chemically, $2-$hydroxyethanoic acid.
MCQ 661 Mark
Most abundant organic compound on earth is:
- ✓Cellulose.
- BSteroids.
- CProtein.
- DLipids.
Answer
View full question & answer→Correct option: A.
Cellulose.
Cellulose.
MCQ 671 Mark
The enzymes hexokinase which catalyses glucose to glucose$-6-$phosphate in glycolysis is inhibited by glucose$-6-$phosphate. This is an example of:
- ✓Feedback allosteric inhibition.
- BNon$-$competitive inhibition.
- CCompetitive inhibition.
- DNone of these.
Answer
View full question & answer→Correct option: A.
Feedback allosteric inhibition.
Feedback allosteric inhibition.
MCQ 681 Mark
Inulin is made up of $.............$ and $.............$
- AGlucose and fructose.
- ✓Glucose and fructose.
- CFructose and mannose.
- DMannose and glucose.
Answer
View full question & answer→Correct option: B.
Glucose and fructose.
Inulin is a polysaccharide made up of glucose and fructose.
MCQ 691 Mark
Which is not consistent with double helical structure of $\text{DNA}?$
- ✓$\ce{A = T, C = G.}$
- BDensity of $\text{DNA}$ decreases on heating.
- C$\ce{A + T/ C + G}$ is not constant.
- DBoth $(a)$ and $(b).$
Answer
View full question & answer→Correct option: A.
$\ce{A = T, C = G.}$
$\ce{A + T/ C + G}$ is not constant.
MCQ 701 Mark
Amino acids are also known as:
- ✓$\alpha-$amino acid.
- B$\beta-$amino acid.
- C$\gamma-$amino acid.
- D$\delta-$amino acid.
Answer
View full question & answer→Correct option: A.
$\alpha-$amino acid.
$\alpha-$amino acid.
MCQ 711 Mark
Which of the following enzyme can form $\ce{RNA}$ from $\ce{DNA:}$
- ARestriction enzyme
- B$\ce{DNA}$ polymerase
- ✓$\ce{RNA}$ polymerase
- DReverse transcriptase
Answer
View full question & answer→Correct option: C.
$\ce{RNA}$ polymerase
$\ce{RNA}$ polymerase
MCQ 721 Mark
Which one contains four pyrimidine bases?
- ✓$\ce{GATCAATGC.}$
- B$\ce{GCUAGACAA.}$
- C$\ce{UAGCGGUAA.}$
- D$\ce{TGCCTAACG.}$
Answer
View full question & answer→Correct option: A.
$\ce{GATCAATGC.}$
$\ce{GATCAATGC.}$
MCQ 731 Mark
Two free ribonucleotide units are interlinked with:
- APeptidebond.
- BCovalent bond.
- CHydrogen bond.
- ✓Phosphodiester bond.
Answer
View full question & answer→Correct option: D.
Phosphodiester bond.
Phosphodiester bond.
MCQ 741 Mark
Which of the following is capable of self replication:
- AA protein molecule
- BA carbohydrate molecule
- CA water molecule
- ✓A nucleic acid
Answer
View full question & answer→Correct option: D.
A nucleic acid
Miescher discovered nucleic acids from pus cells in discarded surgical bands.
He observed that these were acidic in nature.
The two types of nucleic acid were $\text{DNA}$ and $\text{RNA.}$
These are considered as the hereditary unit of the cell.
These carry characters from one generation to the other.
A nucleic acid molecule can act as genetic material because nucleic acids possess the ability of self$-$replication,
i.e., capacity to generate their own copies.
He observed that these were acidic in nature.
The two types of nucleic acid were $\text{DNA}$ and $\text{RNA.}$
These are considered as the hereditary unit of the cell.
These carry characters from one generation to the other.
A nucleic acid molecule can act as genetic material because nucleic acids possess the ability of self$-$replication,
i.e., capacity to generate their own copies.
MCQ 751 Mark
Which of the following is a fat?
- AMustard oil.
- ✓Ghee.
- CSunflower oil.
- DCastor oil.
Answer
View full question & answer→Correct option: B.
Ghee.
Ghee.
MCQ 761 Mark
Insulin is made up of $..........$ and $.........$
- AGlucose and fructose.
- ✓Glucose and fructose.
- CFructose and mannose.
- DMannose and glucose.
Answer
View full question & answer→Correct option: B.
Glucose and fructose.
Insulin is a polysaccharide made up of glucose and fructose.
MCQ 771 Mark
Purines and pyrimidines polymerise to form:
- ANucleoside
- ✓Nucleic acid
- CRibonucleotides
- DAll of the above
Answer
View full question & answer→Correct option: B.
Nucleic acid
Nucleic acids are polymers of nucleotides.
They are formed by joining together of long chains of nucleotides.
$\text{RNA} ($ribonucleic acid$)$ is a polymer of ribonucleotides and is made up of ribonucleotides joined together by phosphodiester bonds.
$\text{DNA} ($deoxyribonucleic acid$)$ is a polymer of deoxyribonucleotides and is made up of deoxyribonucleotides joined together by phosphodiester bonds.
They are formed by joining together of long chains of nucleotides.
$\text{RNA} ($ribonucleic acid$)$ is a polymer of ribonucleotides and is made up of ribonucleotides joined together by phosphodiester bonds.
$\text{DNA} ($deoxyribonucleic acid$)$ is a polymer of deoxyribonucleotides and is made up of deoxyribonucleotides joined together by phosphodiester bonds.
MCQ 781 Mark
Nitrogen is the main constituent of:
- AFats
- ✓Proteins
- CPolyphosphates
- DCarbohydrates
Answer
View full question & answer→Correct option: B.
Proteins
Proteins are the linear chain of amino acids formed by joining together of a number of amino acids through peptide bonds.
The peptide bond between two amino acids is formed by a condensation reaction between amino group of one amino acid and carboxylic group of another amino acid.
The amino acids are amphoteric compounds having both basic $($amino$)$ as well as acidic $($carboxylic$)$ groups.
The amino acids are rich in nitrogen because of the amino group. Protein contains $16\%$ of nitrogen.
The peptide bond between two amino acids is formed by a condensation reaction between amino group of one amino acid and carboxylic group of another amino acid.
The amino acids are amphoteric compounds having both basic $($amino$)$ as well as acidic $($carboxylic$)$ groups.
The amino acids are rich in nitrogen because of the amino group. Protein contains $16\%$ of nitrogen.
MCQ 791 Mark
Which of the following cannot be traced in proteins?
- APhosphorous
- BNitrogen
- ✓Glycerol
- DCarbon
Answer
View full question & answer→Correct option: C.
Glycerol
Glycerol
MCQ 801 Mark
Genes are packaged into a bacterial chromosome by:
- AHistones.
- ✓Basic proteins.
- CAcidic proteins.
- DActin.
Answer
View full question & answer→Correct option: B.
Basic proteins.
Basic proteins.
MCQ 811 Mark
Which of the following influence feedback inhibition of enzyme?
- ✓End product
- BExternal factors
- CEnzyme
- DSubstrate
Answer
View full question & answer→Correct option: A.
End product
End product
MCQ 821 Mark
The nitrogenous organic base purine occurring in $\text{RNA}$ is:
- ACytosine.
- BThymine.
- ✓Guanine.
- DUracil.
Answer
View full question & answer→Correct option: C.
Guanine.
Guanine.
MCQ 831 Mark
One of the similarities between $\text{DNA}$ and $\text{RNA}$ is that both.
- ✓Are polymers of nucleotides.
- BAre capable of replicating.
- CHave similar sugars.
- DHave similar pyrimidine bases.
Answer
View full question & answer→Correct option: A.
Are polymers of nucleotides.
Are polymers of nucleotides.
MCQ 841 Mark
Which one of the following statements about cytochrome $450$ is wrong?
- AIt contains iron.
- ✓It is a coloured cell.
- CIt has an important role in metabolism.
- DIt is an enzyme involved in oxidation reactions.
Answer
View full question & answer→Correct option: B.
It is a coloured cell.
It is a coloured cell.
MCQ 851 Mark
Which of the following groups consists only of polysaccharides?
- ✓Cellulose, Starch, Glycogen.
- BStarch, Lactose, Cellulose.
- CLactose, Starch, Glycogen.
- DStarch, Maltose, Cellulose.
Answer
View full question & answer→Correct option: A.
Cellulose, Starch, Glycogen.
Cellulose, Starch, Glycogen.
MCQ 861 Mark
What replaces thymine in $\text{RNA:}$
- AGuanine
- BAdenine
- ✓Uracil
- DWater
Answer
View full question & answer→Correct option: C.
Uracil
In $\text{RNA,}$ uracil binds to adenine via two hydrogen bonds.
In $\text{DNA,}$ the uracil nucleobase is replaced by thymine.
Uracil could be considered a demethylated form of thymine.
Each nucleotide in $\text{RNA}$ contains a ribose sugar, with carbons numbered $1'$ through $5'$. A base is attached to the $1'$ position, in general, adenine $(A),$ cytosine $(C),$ guanine $(G),$ or uracil $(U).$
Adenine and guanine are purines, cytosine and uracil are pyrimidines.
In $\text{DNA,}$ the uracil nucleobase is replaced by thymine.
Uracil could be considered a demethylated form of thymine.
Each nucleotide in $\text{RNA}$ contains a ribose sugar, with carbons numbered $1'$ through $5'$. A base is attached to the $1'$ position, in general, adenine $(A),$ cytosine $(C),$ guanine $(G),$ or uracil $(U).$
Adenine and guanine are purines, cytosine and uracil are pyrimidines.
MCQ 871 Mark
Which is wrong about nucleic acids?
- A$\text{DNA}$ is single stranded in some viruses.
- B$\text{RNA}$ is double stranded occasionally.
- ✓Length of one helix is $45 \mathring A$ in $\text{B-DNA.}$
- DOne turn of $\text{Z-DNA}$ has $12$ bases.
Answer
View full question & answer→Correct option: C.
Length of one helix is $45 \mathring A$ in $\text{B-DNA.}$
Length of one helix is $45 \mathring A$ in $\text{B-DNA}.$
MCQ 881 Mark
Conjugated proteins containing carbohydrates as prosthetic group are known as:
- AChromoproteins.
- ✓Glycoproteins.
- CLipoproteins.
- DNucleoproteins.
Answer
View full question & answer→Correct option: B.
Glycoproteins.
Glycoproteins.
MCQ 891 Mark
The minimum amount of energy required to initiate a chemical reaction is called:
- AEnzymatic energy.
- ✓Activation energy.
- CSubstrate energy.
- DInitiation energy.
Answer
View full question & answer→Correct option: B.
Activation energy.
The minimum amount of energy required to initiate a chemical reaction is called activation energy.
MCQ 901 Mark
Transamination is:
- ✓Transfer of amino group from amino acid to keto acid
- BOxidation of ammonia
- CAmino-acid destruction
- DNone of the above
Answer
View full question & answer→Correct option: A.
Transfer of amino group from amino acid to keto acid
Transamination reaction is the transfer of amino groups from an amino acid to a keto acid.
The enzyme is transaminase.
It helps in formation of different amino acids which are not formed by reductive amination.
The enzyme is transaminase.
It helps in formation of different amino acids which are not formed by reductive amination.
MCQ 911 Mark
The plant proteinases or endopeptidases enzyme is:
- AUrease
- ✓Papain
- CPepsin
- DTrypsin
Answer
View full question & answer→Correct option: B.
Papain
Papain is the only protein that is not found in humans.
It is found in plants like papaya and the main function of papain is breakdown of peptide bonds in protein.
It is found in plants like papaya and the main function of papain is breakdown of peptide bonds in protein.
MCQ 921 Mark
$...............$ causes protein to denature:
- AWater
- ✓Heat
- CEnzyme
- DPressure
Answer
View full question & answer→Correct option: B.
Heat
One of the common methods of protein denaturation is heat.
For example, boiling of egg denatures egg white.
A denatured protein can no longer perform its normal biological role.
For example, boiling of egg denatures egg white.
A denatured protein can no longer perform its normal biological role.
MCQ 931 Mark
The $\text{RNA}$ that picks up specific amino acids from the amino acid pool in the cytoplasm to ribosome during protein synthesis is called:
- A$\text{mRNA.}$
- ✓$\text{tRNA.}$
- C$\text{rRNA.}$
- DCarrier $\text{RNA.}$
Answer
View full question & answer→Correct option: B.
$\text{tRNA.}$
$\text{tRNA.}$
MCQ 941 Mark
What is a prosthetic group of a protein:
- AAmino acid
- BPeptide chain
- CPolypeptide chain
- ✓Non$-$protein component
Answer
View full question & answer→Correct option: D.
Non$-$protein component
Prosthetic groups are cofactors that bind tightly to proteins or enzymes.
It is a specific non$-$polypeptide required for the biological function of some proteins.
The prosthetic group may be organic $($such as vitamin, sugar or lipid$)$ or inorganic $($such as metal ion$),$ but is not composed of amino acids.
It is a specific non$-$polypeptide required for the biological function of some proteins.
The prosthetic group may be organic $($such as vitamin, sugar or lipid$)$ or inorganic $($such as metal ion$),$ but is not composed of amino acids.
MCQ 951 Mark
Which one of the following is body building material:
- ✓Protein
- BSugar
- CMineral salts
- DFat
Answer
View full question & answer→Correct option: A.
Protein
Proteins are building blocks of life.Sugar $($meaning carbohydrate$)$ is required for energy.
Mineral salts can be used for various functions like building strong bones, etc.
Fats are also required for energy.
Fats can be stored in the body and can be used when carbohydrates are exhausted.
Mineral salts can be used for various functions like building strong bones, etc.
Fats are also required for energy.
Fats can be stored in the body and can be used when carbohydrates are exhausted.
MCQ 961 Mark
Bonds that do not exist in tertiary structure of proteins.
- ✓Phosphodiester bonds.
- BHydrophobic etnractions.
- CIonic bonds.
- DCovalent bonds.
Answer
View full question & answer→Correct option: A.
Phosphodiester bonds.
Phosphodiester bonds.
MCQ 971 Mark
A nucleotide is formed of:
- ✓Nitrogen base, sugar and phosphate.
- BPyrimidine, sugar and phosphate.
- CPurine, sugar and phosphate.
- DPurine, pyrimidine and phosphate.
Answer
View full question & answer→Correct option: A.
Nitrogen base, sugar and phosphate.
Nitrogen base, sugar and phosphate.
MCQ 981 Mark
Cofactor $($coenzyme$)$ is a part of holoenzyme it is:
- ALoosely attached inorganic part.
- BAccessory non$-$protein substance attached firmly.
- ✓Loosely attached organic part.
- DNone of the above.
Answer
View full question & answer→Correct option: C.
Loosely attached organic part.
Loosely attached organic part.
MCQ 991 Mark
When you take cells or tissue pieces and grind them with an acid in a mortar and pestle, all the small biomolecules dissolve in the acid. Proteins, polysaccharides and nucleic acids are insoluble in mineral acid and get precipitated. The acid soluble compounds include aminoacids, nucleosides, small sugars etc. When one adds a phosphate group to a nucleoside, one gets another acid soluble biomolecule called.
- ANitrogen base.
- BAdenine.
- CSugar phosphate.
- ✓Nucleotide.
Answer
View full question & answer→Correct option: D.
Nucleotide.
When a phosphate group is added to a nucleoside, it becomes a nucleotide.
MCQ 1001 Mark
Which of the following is not a part of enzyme but it activates the enzyme?
- ✓$K$
- B$C$
- C$N$
- D$Si$
Answer
View full question & answer→Correct option: A.
$K$
$K$