Questions

Assertion (A) & Reason (B) MCQ

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31 questions · auto-graded multiple-choice test.

MCQ 11 Mark
Two statements are given$-$ one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $\text{(a), (b), (c)}$ and $(d)$ as given below:
Assertion $(A):\ $ Sucrose is a non$-$reducing sugar.
Reason $(R):\ $ Reducing groups of glucose and fructose are involved in glycosidic bond formation.
  • Both Assertion $(A)$ and Reason $(R)$ are correct statements, and Reason $(R)$ is the correct explanation of the Assertion $(A).$
  • B
    Both Assertion $(A)$ and Reason $(R)$ are correct statements, but Reason $(R)$ is not the correct explanation of the Assertion $(A).$
  • C
    Assertion $(A)$ is correct, but Reason $(R)$ is incorrect statement.
  • D
    Assertion $(A)$ is incorrect, but Reason $(R)$ is correct statement.
Answer
Correct option: A.
Both Assertion $(A)$ and Reason $(R)$ are correct statements, and Reason $(R)$ is the correct explanation of the Assertion $(A).$
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MCQ 21 Mark
Two statements are given$-$ one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $\text{(a), (b), (c)}$ and $(d)$ as given below:
Assertion $(A):\ $ Sucrose is a non$-$reducing sugar.
Reason $(R):\ $ Sucrose has glycosidic linkage.
  • A
    Both Assertion $(A)$ and Reason $(R)$ are correct statements, and Reason $(R)$ is the correct explanation of the Assertion $(A).$
  • Both Assertion $(A)$ and Reason $(R)$ are correct statements, but Reason $(R)$ is not the correct explanation of the Assertion $(A).$
  • C
    Assertion $(A)$ is correct, but Reason $(R)$ is incorrect statement.
  • D
    Assertion $(A)$ is incorrect, but Reason $(R)$ is correct statement.
Answer
Correct option: B.
Both Assertion $(A)$ and Reason $(R)$ are correct statements, but Reason $(R)$ is not the correct explanation of the Assertion $(A).$
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MCQ 31 Mark
Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Vitamin $D$ can be stored in our body.
Reason: Vitamin $D$ is fat soluble vitamin.
  • Assertion and reason both are correct statements and reason explains the assertion.
  • B
    Both assertion and reason are wrong statements.
  • C
    Assertion is correct statement and reason is wrong statement.
  • D
    Assertion is wrong statement and reason is correct statement.
Answer
Correct option: A.
Assertion and reason both are correct statements and reason explains the assertion.
Vitamin $D$ can be stored in our body because it is a fat soluble vitamin.
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MCQ 41 Mark
Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: All naturally occurring $\alpha -$aminoacids except glycine are optically active.
Reason: Most naturally occurring amino acids have $L-$configuration.
  • A
    Assertion and reason both are correct statements and reason explains the assertion.
  • B
    Both assertion and reason are wrong statements.
  • C
    Assertion is correct statement and reason is wrong statement.
  • Assertion and reason both are correct statements but reason does not explain assertion
Answer
Correct option: D.
Assertion and reason both are correct statements but reason does not explain assertion
All amino acids except glycine contain at least one chiral carbon.
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MCQ 51 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Insulin is water soluble.
Reason: Insulin is a globular protein.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Insulin is a globular protein This protein has three-dimensional folded structure. These are stabilised by internal hydrogen bonding, hence, they are water soluble.
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MCQ 61 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: $\alpha-$Amino acids exist as dipolar ions or zwitter ions.
Reason: $\alpha-$Amino acids are the building blocks of proteins.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
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MCQ 71 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: $\text{DNA}$ has a double helix structure.
Reason: The two strands in a $\text{DNA}$ molecule are exactly similar.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: C.
Assertion is correct statement but reason is wrong statement.
The two strands in a $\text{DNA}$ molecule are not exactly similar but are complimentary.
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MCQ 81 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Glucose and fructose are reducing sugars.
Reason: Glucose and fructose contain a free aldehydic and ketonic group adjacent to a $> \text{CHOH}$ group respectively.
  • Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: A.
Assertion and reason both are correct statements and reason is correct explanation for assertion.
Reducing sugars contain a free aldehydic or ketonic group adjacent to a $> \text{CHOH}$ group and reduce Tollen's reagent, Schiff's reagent or Benedict's solution.
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MCQ 91 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Fructose reduces Fehling's solution and Tollens' reagent.
Reason: Fructose does not contain any aldehyde group.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Fructose on warming with dilute alkali, gives rise to an equilibrium mixture of glucose, fructose and mannose. The ability of fructose to reduce Fehling solution and Tollens' reagent is probably due to the isomerisation of fructose to glucose and man nose $($this is called Lobry de Bruyn and Elkenstein rearrangement$).$
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MCQ 101 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Glycine exists as zwitter ion but $o-$ and $p-$aminobenzoic acids do not.
Reason: Due to the presence of $-NH_2$ and $-\text{COOH}$ group within the same molecule, they neutralise each other and hence$, n-$amino acids exist as dipolar ions or zwitter ions.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
In $o-$ or $p-$aminobenzoic acids, the lone pair of electrons on the $-\mathrm{NH}_2$ group is donated towards the benzene ring. As a result, the basic character of $-\mathrm{NH}_2$ group and acidic character of $-\text{COOH}$ group decreases. Therefore, the weakly acidic $- \text{COOH}$ group cannot transfer $\mathrm{H}^{+}$ ion to the weakly basic $-\mathrm{NH}_2$ group therefore$, o$ and $p-$aminobenzoic acids do not exist as zwitter ion.
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MCQ 111 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: The specific rotation of a freshly prepared solution of $\alpha-$glucose decreases from $+ 112^\circ $ to $52.7^\circ $ while that of $\beta-$glucose increases from $+ 19^\circ $ to $52.7^\circ .$
Reason: The change in specific rotation of an optically active compound with time to an equilibrium value is called mutarotation.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Glucose exists in two forms, i.e. $ti-D:\ $ glucose with a specific rotation of $+112^\circ $ and $\alpha-D$ glucose with a specific rotation of $+ 19^\circ .$ However, when either of these two fonns is dissolved in water and allowed to stand, it gets converted into the same equilibrium mixture of both the $\alpha-$ and $\beta-$forms with a small amount of open chain form. As a result of this equilibrium, the specific rotation of a freshly prepared solution of $\alpha-$glucose decreases from $+ 112^\circ $ to $52.7^\circ $ while th at of $\beta-$glucose increases from $+ 19^\circ $ to $52. 7^\circ .$
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MCQ 121 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Amino acids are insoluble in benzene and ether.
Reason: Amino acids exist as zwitter ions.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Amino acids are soluble in polar solvents like $\ce{H_2O, NaOH}$ and $\text{HCI}$ and insoluble in non$-$polar solventslike benzene, ether, etc.
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MCQ 131 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Glucose and fructose give the same osazone.
Reason: During osazone formation stereochemistry at $C_1$ and $C_2$ is destroyed.
  • Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: A.
Assertion and reason both are correct statements and reason is correct explanation for assertion.
Glucose and fructose differ from each other only at $C_1$ and $C_2$ positions.
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MCQ 141 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: $\text{DNA}$ undergoes replication.
Reason: $\text{DNA}$ contains cytosine and thymine as pyrimidine bases.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
The genetic information of the cell is contained in the sequence of base $\text{A, T, G}$ and $C$ in $\text{DNA}$ molecule when a cell divides$, \text{DNA}$ molecules replicate and make exact copies of themselves so that each daughter cell will have $\text{DNA}$ identical to that of the parent cell.
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MCQ 151 Mark

Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: $\beta-$glycosidic linkage is present in maltose,

Reason: Maltose is composed of two glucose units in which $C_1$ of one glucose unit is linked to $C_4$ of another glucose unit.
  • A
    Assertion and reason both are correct statements and reason explains the assertion.
  • B
    Both assertion and reason are wrong statements.
  • C
    Assertion is correct statement and reason is wrong statement.
  • Assertion is wrong statement and reason is correct statement.
Answer
Correct option: D.
Assertion is wrong statement and reason is correct statement.

Maltose is composed of two $D-$glucose units in which $C_1$ of one glucose $(I)$ is linked to $C_4$ of another glucose unit.
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MCQ 161 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Cysteine can cross link peptide chains.
Reason: Amino acids are classified as essential and non$-$essential amino acids.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Cysteine can cross link peptide chains through disulphide bridge. Cross linking by disulphide bridge can occur either between the distant, properly oriented parts of the same polypeptide chain $($as in oxytocin or vasopressin$)$ or between different polypeptide chains.
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MCQ 171 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
 Assertion: Uracil occurs in $\text{DNA}.$
Reason: $\text{DNA}$ undergoes replication.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • Assertion is wrong statement but reason is correct statement.
Answer
Correct option: D.
Assertion is wrong statement but reason is correct statement.
Uracil occurs in $\text{RNA}$
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MCQ 181 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Solubility of proteins is minimum at the isoelectric point.
Reason: At isoelectric point, protein molecule behaves as a zwitter ion.
  • Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: A.
Assertion and reason both are correct statements and reason is correct explanation for assertion.
At isoelectric point, protein molecules behave as zwitter ions and hence, do not move toward any electrode or act as neutral molecules. This reduces their solubility to minimum and thus, helps in their separation and purification
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MCQ 191 Mark
Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Glycine must be taken through diet.
Reason: It is an essential amino acid.
  • A
    Assertion and reason both are correct statements and reason explains the assertion.
  • Both assertion and reason are wrong statements.
  • C
    Assertion is correct statement and reason is wrong statement.
  • D
    Assertion is wrong statement and reason is correct statement.
Answer
Correct option: B.
Both assertion and reason are wrong statements.
Glycine can be synthesized by the body and is a non$-$essential amino acid.
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MCQ 201 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Alpha $(\alpha)-$ amino acids exist as internal salt in solution as they have amino and carboxylic acid groups in near vicinity.
Reason: $H^+$ ion given by carboxylic group $\ce{(-COOH)}$ is captured by amino group $\ce{(-NH_2)}$ having lone pair of electrons.
  • Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: A.
Assertion and reason both are correct statements and reason is correct explanation for assertion.
$\ce{NH_2 - CH_2 - COOH}$ is a typical a $-$ amino acid.
In solution it exists as, internal salt or zwitter ion,
$(\stackrel{{+}}{\hbox{ NH}}_3)-\text{CH}_2-\text{COO}^-)$
because the proton $(H^+)$ of $-\ce{PCOOH}$ group is captured by $-\ce{NH_2}$ group as $\ce{NH_2}$ has a lone pair of electrons on $N$ atom.
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MCQ 211 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Haemoglobin is a globular protein.
Reason: Globular proteins are insoluble in water.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: C.
Assertion is correct statement but reason is wrong statement.
Globular proteins have weak intermolecular forces of attraction and hence they are soluble in water.
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MCQ 221 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Glucose gives a reddish-brown precipitate with Fehling's solution.
Reason: Reaction of glucose with Fehhng's solution gives $\text{CuO}$ and gluconic acid.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: C.
Assertion is correct statement but reason is wrong statement.
$\ \text{CHO}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{COOH}\\\ \ |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\text{CHOH}_4)\xrightarrow[\text{Fehling Benedict solution}]{\text{Cu}^{2+}}(\text{CHOH})_4+\text{Cu}_2\text{F}\downarrow\\\ \ |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\ \ \ \ \ \ \ \ \ \ \ \ \text{Red brown}\\\ \text{CH}_2\text{OH}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_2\text{OH}\\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{Gluconic Acid}$
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MCQ 231 Mark
Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: In presence of enzyme, substrate molecule can be attacked by the reagent effectively.
Reason: Active sites of enzymes hold the substrate molecule in a suitable position.
  • Assertion and reason both are correct statements and reason explains the assertion.
  • B
    Both assertion and reason are wrong statements.
  • C
    Assertion is correct statement and reason is wrong statement.
  • D
    Assertion is wrong statement and reason is correct statement.
Answer
Correct option: A.
Assertion and reason both are correct statements and reason explains the assertion.
In presence of enzyme, substrate molecule can be attacked by the reagent effectively because active sites of enzymes hold the substrate molecule in a suitable position.
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MCQ 241 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: $\beta-$pleated sheet structure of protein shows maximum extension.
Reason: Intermolecular hydrogen bonding is present in them.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
In $\beta-$pleated sheet structure, the polypeptide chains are held together by intermolecular $H-$bonds. Extension and contraction of $\beta-$pleated sheet structure of protein depends on the size of $R.$
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MCQ 251 Mark
Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: $D(+)-$Glucose is dextrorotatory in nature.
Reason: $'D\ ’$ represents its dextrorotatory nature.
  • A
    Assertion and reason both are correct statements and reason explains the assertion.
  • B
    Both assertion and reason are wrong statements.
  • Assertion is correct statement and reason is wrong statement.
  • D
    Assertion is wrong statement and reason is correct statement.
Answer
Correct option: C.
Assertion is correct statement and reason is wrong statement.
Glucose is correctly named as $D(+)-$glucose$. 'D\ ’$ before the name of glucose represents the configuration whereas $'(+)\ ’$ represents dextrorotatory nature of the molecule. The letters $'D\ ’$ or $'L\ ’$ before the name of any compound indicate the relative configuration of a particular stereoisomer.
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MCQ 261 Mark
Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Deoxyribose, $\mathrm{C}_5 \mathrm{H}_{10} \mathrm{O}_4$ is not a carbohydrate.
Reason: Carbohydrates are hydrates of carbon so compounds which follow $\mathrm{C}_x\left(\mathrm{H}_2 \mathrm{O}\right)$ y formula are carbohydrates.
  • A
    Assertion and reason both are correct statements and reason explains the assertion.
  • Both assertion and reason are wrong statements.
  • C
    Assertion is correct statement and reason is wrong statement.
  • D
    Assertion is wrong statement and reason is correct statement.
Answer
Correct option: B.
Both assertion and reason are wrong statements.
Complete hydrolysis of $\text{DNA}\ ($or $\text{RNA)}$ yields a pentose sugar, phosphoric acid and nitrogen containing hetero$-$cyclic compounds $($called bases$).$ In $\text{DNA}$ molecules, the sugar moiety is $D-2-$ Deoxyribose.
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MCQ 271 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Nucleotides are phosphate esters of nucleosides.
Reason: The various nucleotides in nucleic acids are linked either through purine or pyrimidine bases.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: C.
Assertion is correct statement but reason is wrong statement.
The various nucleotides in nucleic acids are linked through phosphate ester groups.
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MCQ 281 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Valine is an essential amino acid.
Reason: The lack of essential amino acids in the diet causes Kwashiorkor.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Valine is an essential amino acid. The amino acids which the body cannot synthesize are called essential amino acid.
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MCQ 291 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Tollens' reagent, Benedict's solution and Fehling's solution are reducing agents.
Reason: Mild oxidising agents like chlorine or bromine water convert glucose into gluconic acid.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • B
    Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • Assertion is wrong statement but reason is correct statement.
Answer
Correct option: D.
Assertion is wrong statement but reason is correct statement.
Benedict's solution, Tollens' reagent, Fehllng's solution etc. are mild oxidising agents. They oxidise the aldoses and ketoses to the corresponding acids and get themselves reduced.
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MCQ 301 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Glucose when treated with $\ce{CH_3OH}$ in presence of dry $\ce{HCI}$ gas gives ct $-$ and methyl glucosides.
Reason: Glucose reacts with phenyl hydrazine to form crystalline osazone.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Because of the ring structure $C_1$ in glucose becomes chiral and hence glucose exists in two stereoisomeric forms,
i.e., $\alpha-$ and $\beta-, $ corresponding to each stereoisomeric fonn glucose forms two methyl glucosides,
i.e., $\alpha- $ and $\beta-$ methyl glucosides.
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MCQ 311 Mark
In these questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion: Disruption of the native structure of a protein is called denaturation.
Reason: The change in colour and appearance of egg during cooking is due to denaturation.
  • A
    Assertion and reason both are correct statements and reason is correct explanation for assertion.
  • Assertion and reason both are correct statements but reason is not correct explanation for assertion.
  • C
    Assertion is correct statement but reason is wrong statement.
  • D
    Assertion is wrong statement but reason is correct statement.
Answer
Correct option: B.
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
Due to denaturation, a protein loses its biological activity. During denaturation the protein molecule uncoils from a more random conformation and precipitates from the solution.
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