Chapter 31

Methyl- \(\alpha\)-D-glucoside and methyl-\beta-D-glucoside are (a) epimers (b) anomers (c) enantiomers (d) conformational diastereomers

Which of the following statements is correct? (a) the metal ion present in vitamin \(\mathrm{B}_{12}\) is \(\mathrm{Zn}^{2+}\) (b) in photosynthesis \(\mathrm{CO}_{2}\) and \(\mathrm{H}_{2} \mathrm{O}\) are converted into carbohydrates in presence of sunlight (c) in haemoglobin the oxidation state of \(\mathrm{Fe}\) is \(+6\). (d) methyl salicylate is known as aspirin

The number of hydrogen bonds formed between in the sequence of a stretch of a double helical DNA 5'ATGCCTAA3' is (a) 15 (b) 19 (c) 29 (d) 12

Consider the following statements about sucrose. 1\. hydrolysis of sucrose with dilute acid yields an equimolar mixture of D-glucose and D-fructose 2\. acid hydrolysis of sucrose is accompanied by a change in optical rotation 3\. in sucrose, the glycosidic linkage is between \(\mathrm{C}-1\) of glucose and \(\mathrm{C}-2\) of fructose 4\. aqueous solution of sucrose exhibits mutarotation Which of the statements are correct? (a) 1 and 2 only (b) 2 and 3 only (c) 1,2 and 3 (d) 1,3 and 4

Glucose and fructose give the same osazone. One may, therefore conclude that (a) the structures of glucose and fructose have mirror image relationship (b) glucose and fructose have identical structures (c) the structures of glucose and fructose differ only in those carbon atoms which take part in osazone formation (d) glucose and fructose are anomers

Consider the following statements about proteins: 1\. all natural amino acids which are constituents of proteins are \(\alpha\)-amino acids 2\. \(\alpha\)-amino acids are all optically active and have the L-configuration 3\. an especially favourable conformation for the peptide linkage in proteins is the \(\alpha\)-helix arrangement. 4\. \(\alpha\)-amino acids are connected by ester linkages of these statements (a) 1 and 3 are correct (b) 1 and 2 are correct (c) 2 and 3 are correct (d) 2,3 and 4 are correct

Which of the following is true? (i) sucrose is a non reducing agent (ii) glucose is oxidized by bromine water (iii) glucose rotates plane polarized light in clockwise direction (iv) fructose is oxidized by bromine water Select the correct answer during the coded given below (a) (i), (ii), (iii) (b) (i), (ii) only (c) (ii), (iii) only (d) (i) (iv) only

Consider the following statements about amino acids: (1) nitrous acid liberates nitrous oxide from amino acids (2) an important sensitive test for the detection of amino acids is the ninhydrin colour test (3) glycine is the only amino acid which does not possess a chiral centre. (4) all the natural amino acids that occur as constituents of proteins belong to the L-series

Which statements are correct about peptide bond? (1) - CONH-group is planar (2) \(\mathrm{C}-\mathrm{N}\) bond length in protein is longer than usual bond length of \(\mathrm{C}-\mathrm{N}\) bond (3) C-N bond length in protein is smaller than usual bond length of \(\mathrm{C}-\mathrm{N}\) bond (a) 2 and 3 (b) 1 and 2 (c) 2 only (d) 1 and 3

Consider the following statements about carbohydrates: 1\. Bromine water can be used to differentiate an aldose from a ketose 2\. All monosaccharides, whether aldose or ketose, are reducing sugars 3\. Osazone formation destroys the configuration about C-2 of an aldose, but does not affect the configuration of the rest of the molecule 4\. A pair of diastereomeric aldoses which differ only in configuration about C-2 is termed as pair of anomers Which of the above statements are correct? (a) 1 and 4 (b) 2 and 4 (c) 1,2 and 3 (d) 2,3 and 4

An aldose is oxidized separately by \(\mathrm{Br}_{2} / \mathrm{H}_{2} \mathrm{O}\) (condition-A) and by \(\mathrm{HNO}_{3}\) (condition-B). Which of the following is the correct combination of the products formed? (a) condition-A gives aldaric acid while condition-B yields a mixture of aldonic and aldaric acids (b) condition-A gives aldonic acid while condition-B yields a mixture of aldonic and aldaric acids (c) condition-A gives aldaric acid while condition-B yields aldonic acid (d) condition-A gives aldonic acid while condition-B yields aldaric acid

Which of the following give the same osazone on treatment with phenyl hydrazine? (a) Glucose (b) Galactose (c) Fructose (d) Mannose

If \(\mathrm{C}-5\) carbon of \(\mathrm{D}-\) glucose is inverted the new compound is related to the parent compound as (a) Enantiomer (b) Epimer (c) Anomer (d) diastereomer

Which of the following statements are correct? (a) All monosaccharides whether aldose or ketose act as reducing sugars. (b) Bromine water can be used to differentiate between aldoses and ketoses. (c) A pair of diastereomeric aldoses which differ only in configuration about \(\mathrm{C}_{2}\) is termed as a pair of anomers. (d) Osazone formation destroys the configuration about \(\mathrm{C}_{2}\) of an aldose but does not affect the configuration of the rest of the molecule.

The characteristics of glycosidic linkage is/ are (a) ether linkage of sugar (b) it is hydrolysed by acid (c) it is hydrolysed by alkali (d) it is also hydrolysed by specific enzyme

Which of the following statement(s) is/are correct? (a) The smallest aldose to form a cyclic hemi- acetal must have 4 carbon atoms. (b) D- glucose and D- fructose can be differentiated using Benedict's solution (c) When D- galactose is oxidised by \(\mathrm{HNO}_{3}\), it gives a meso isomer. (d) Aldoses react with Fehling's solution and \(\mathrm{PhNHNH}_{2}\) but not with \(\mathrm{NaHSO}_{3}\).

Primary structure of protein involves (a) Vander Waal's interaction (b) Hydrogen bonds (c) Peptide bonds (d) Disulphide bonds

Which of the following has a glucosidic linkage? (a) Amylose (b) Sucorse (c) Maltose (d) Galactose

The following amino acid has characteristic pKa values \(\mathrm{pK}_{\mathrm{a}(1)}=2.18 ; \mathrm{pK}_{\mathrm{a}(2)}=8.95\) and \(\mathrm{pK}_{a(3)}=10.79\) The isoelectric point pI of the above amino acid is (a) \(5.56\) (b) \(9.87\) (c) \(11.13\) (d) \(12.97\)

Which of the following cannot be oxidized by bromine water ? (a) D- glycerladehyde (b) D- arabinose (c) L- fructose (d) L- glucose

Fructose on oxidation with conc. HNO \(_{3}\) gives (a) Tartaric acid (b) Saccharic acid (c) Glycolic acid (d) Both (a) and (c)

Match the following $$ \begin{array}{ll} \hline \text { Column-I } & \text { Column-II } \\ \hline \text { (a) Glycine } & \text { (p) Forms chloroacetic } \\ \text { acid with NOCl } \\ \text { (b) Lysine } & \text { (q) Neutral } \\ \text { (c) Proline } & \text { (r) Optically inactive } \\ \text { (d) Glutamic acid } & \text { (s) Basic } \\ \text {} & \text { (t) Isoelectric point } \end{array} $$

Match the following $$ \begin{array}{ll} \hline \text { Column-I } & \text { Column-II } \\ \hline \text { (a) Glucose } & \text { (p) Tollen's reagent } \\ \text { (b) Acetaldehyde } & \text { (q) Bromine water } \\ \text { (c) Sucrose } & \text { (r) Phenyl hydrazine } \\ \text { (d) Maltose } & \text { (s) Disaccharide } \\ & \text { (t) Ammonia } \end{array} $$

Match the following $$ \begin{array}{ll} \text { Column-I } & \text { Column-II } \\ \hline \text { (a) Cellulose } & \text { (p) Anomers } \\ \text { (b) } \alpha-\text { D glucose and } & \text { (q) Epimers } \\ \beta-\text { D - glucose } & \\ \text { (c) Glucose and } & \text { (r) Polymer } \\ \text { Mannose } & \\ \text { (d) Protein } & \text { (s) Can be hydrolysed } \\ & \text { (t) Monomers } \\ \hline \end{array} $$

Number of anomers formed when glucose forms its ring structure is

Number of molecules of phenyl hydrazine required to convert a mole of glucose into its osazone is/are

The number of dipeptides possible with three different amino acids combined are

An amino acid has one amino group and one acidic group. If its pKa values are 5 and 3, what will be its isoelectric point?

The number of monosaccharide molecules formed during hydrolysis from one mole of raffinose is

Number of chiral carbon atoms in \(\mathrm{D}(+)\) glucose is

RNA contains (a) ribose sugar and thymine (b) ribose sugar and uracil

The reason for double helical structure of DNA is operation of (a) van der waals forces (b) hydrogen bonding (c) dipole-dipole moment (d) electrostatic attractions

Complete hydrolysis of cellulose gives (a) D-fructose (b) D-glucose (c) D-ribose (d) L-glucose

Insulin production and its action in human body is responsible for the level of diabetes. This compound belongs to which of the following categories? (a) an enzyme (b) an antibiotic (c) a hormone (d) a co- enzyme

In both DNA and RNA heterocyclic base and phosphate ester linkages are at (a) \(\mathrm{C}_{5}{\underline{\phantom{xx}}}^{\prime}\) and \(\mathrm{C}_{2}\) ' respectively of the sugar molecule (b) \(\mathrm{C}_{2}\) and \(\mathrm{C}_{5}^{2}\) ' respectively of the sugar molecule (c) \(\mathrm{C}_{1}^{-}\)and \(\mathrm{C}_{5}\), respectively of the sugar molecule (d) \(\mathrm{C}_{5}{\underline{\phantom{xx}}}^{\prime}\) and \(\mathrm{C}_{1}\), respectively of the sugar molecule

The term anomers of glucose refers to (a) isomers of glucose that differ in configurations at carbons one and four (C-1 and C-4) (b) a mixture of (d)-glucose and (L)-glucose (c) enantiomers of glucose (d) isomers of glucose that differ in configuration at carbon one (C-1)

The pyrimidine bases present in DNA are (a) cytosine and adenine (b) cytosine and guanine (c) cytosine and thymine (d) cytosine and uracil

\(\alpha\)-D-( \(+\) )-glucose and \(\beta\)-D-( \(+\) )-glucose are (a) Conformers (b) Epimers (c) Anomers (d) Enantiomers

The two functional groups present in a typical carbohydrate are: (a) \(-\mathrm{CHO}\) and \(-\mathrm{COOH}\) (b) \(>\mathrm{C}=\mathrm{O}\) and \(-\mathrm{OH}\) (c) \(-\mathrm{OH}\) and \(-\mathrm{CHO}\) (d) \(-\mathrm{OH}\) and \(-\mathrm{COOH}\)

Biuret test is not given by (a) carbohydrates (b) polypeptides (c) urea (d) Proteins

The presence or absence of hydroxyl group on which carbon atom of sugar differentiates RNA and DNA? (a) \(2^{\text {nd }}\) (b) \(3^{\text {nd }}\) (c) \(4^{\text {th }}\) (d) \(1^{\text {st }}\)

Which of the following compounds can be detected by Molisch's test? (a) Amines (b) Sugars (c) Nitro compounds (d) Primary alcohols

Which one of the following statements is correct? [2012] (a) All amino acids except glycine are optically active (b) All amino acids are optically active (c) All amino acids except lysine are optically active (d) All amino acids except glutamic acid are optically acitve

Synthesis of each molecule of glucose in photosynthesis involves: (a) 8 molecules of ATP (b) 6 molecules of ATP (c) 18 molecules of ATP (d) 10 molecules of ATP

Which one of the following bases is not present in DNA ? (a) Cytosine (b) Thymine (c) Quinoline (d) Adenine

Which of the vitamins given below is water soluble? (a) Vitamin C (b) Vitamin D (c) Vitamin E (d) Vitamin \(\mathrm{K}\)

Thiol Group is present in? (a) Cystine (b) Cysteine (c) Cytosine (d) Methionine