Chemistry · Textbook solutions

Biomolecules

Every solved example, exercise, and miscellaneous question, in the order the textbook teaches them. Plus every board question asked from this chapter. · 33 questions

Intext Questions

8 q

Intext 10.1 $Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.$
Intext 10.2 $What are the expected products of hydrolysis of lactose?$
Intext 10.3 $How do you explain the absence of aldehyde group in the pentaacetate of D-glucose?$
Intext 10.4 $The melting points and solubility in water of amino acids are generally higher than that of the corresponding halo acids. Explain.$
Intext 10.5 $Where does the water present in the egg go after boiling the egg?$
Intext 10.6 $Why cannot vitamin C be stored in our body?$
Intext 10.7 $What products would be formed when a nucleotide from DNA containing thymine is hydrolysed?$
Intext 10.8 $When RNA is hydrolysed, there is no relationship among the quantities of different bases obtained. What does this fact suggest about the structure of RNA?$

Exercises

25 q

Ex 10.1 $What are monosaccharides?$
Ex 10.2 $What are reducing sugars?$
Ex 10.3 $Write two main functions of carbohydrates in plants.$
Ex 10.4 $Classify the following into monosaccharides and disaccharides. Ribose, 2-deoxyribose, maltose, galactose, fructose and lactose.$
Ex 10.5 $What do you understand by the term glycosidic linkage?$
Ex 10.6 $What is glycogen? How is it different from starch?$
Ex 10.7 $What are the hydrolysis products of (i) sucrose and (ii) lactose?$
Ex 10.8 $What is the basic structural difference between starch and cellulose?$
Ex 10.9 $\text{HI}$
Ex 10.10 $Enumerate the reactions of D-glucose which cannot be explained by its open chain structure.$
Ex 10.11 $What are essential and non-essential amino acids? Give two examples of each type.$
Ex 10.12 $Define the following as related to proteins (i) Peptide linkage (ii) Primary structure (iii) Denaturation.$
Ex 10.13 $What are the common types of secondary structure of proteins?$
Ex 10.14 $\alpha$
Ex 10.15 $Differentiate between globular and fibrous proteins.$
Ex 10.16 $How do you explain the amphoteric behaviour of amino acids?$
Ex 10.17 $What are enzymes?$
Ex 10.18 $What is the effect of denaturation on the structure of proteins?$
Ex 10.19 $How are vitamins classified? Name the vitamin responsible for the coagulation of blood.$
Ex 10.20 $Why are vitamin A and vitamin C essential to us? Give their important sources.$
Ex 10.21 $What are nucleic acids? Mention their two important functions.$
Ex 10.22 $What is the difference between a nucleoside and a nucleotide?$
Ex 10.23 $The two strands in DNA are not identical but are complementary. Explain.$
Ex 10.24 $Write the important structural and functional differences between DNA and RNA.$
Ex 10.25 $What are the different types of RNA found in the cell?$

What the board has asked from this chapter

Questions per paper · 21 papers · 2023 to 2026

Bars average the full papers of each year. 80 further questions come from set variants and are listed below.

2026

50 q

1 $In the ring structure of fructose, the anomeric carbon is$
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Carbohydrates
9 $\beta$
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Carbohydrates
10 $Each polypeptide in a protein has amino acids linked with each other in a specific sequence and it is this sequence of amino acids that is said to be :$
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Proteins
10 $The base which is present in DNA but not in RNA is :$
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Nucleic Acids
11 $\alpha$
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Proteins
11 $On hydrolysis, which of the following carbohydrates gives only glucose ?$
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Carbohydrates
11 $Identify the polysaccharide among the following :$
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Carbohydrates
11 $Nucleic acids are polymers of :$
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Nucleic Acids
11 $An example of non-reducing sugar is$
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Carbohydrates
12 $Which of the following reactions is not explained by the open chain structure of glucose ?$
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Carbohydrates
12 $Which of the following is a water-soluble vitamin ?$
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Vitamins
12 $The deficiency of which of the following vitamins causes increased fragility of red blood cells and muscular weakness :$
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Vitamins
12 $On hydrolysis, which of the following carbohydrates gives only glucose ?$
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Carbohydrates
12 $The polypeptide chain in a protein has amino acids linked with each other in a specific sequence. This specific sequence of amino acids is called :$
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Proteins
For Questions number 13 to 16, two statements are given — one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.
13 $Assertion (A) : D (+) - Glucose is dextrorotatory in nature. Reason (R) : (+) represents dextrorotatory nature and D represents the configuration.$
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Carbohydrates
For questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below :
15 $\mathrm{H_2N - OH}$
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Carbohydrates
For questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below :
16 $\mathrm{H_2N-OH}$
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Carbohydrates
For question number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below :
16 $Assertion (A) : Glucose gets oxidized to six carbon gluconic acid on reaction with bromine water. Reason (R) : The carbonyl group is absent in the open chain structure of glucose.$
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Carbohydrates
For questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below :
16 $Assertion (A) : The two strands of DNA are complementary to each other. Reason (R) : The hydrogen bonds are formed between specific pairs of bases.$
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Nucleic Acids
18 $What is the effect of denaturation on the structure of proteins ? What are the common types of secondary structures of proteins ?$
Proteins
19 $Name the sugar present in sugarcane. What are the hydrolysis products of this sugar ? Is this sugar a reducing sugar ?$
Carbohydrates
20 $(a) What are the products obtained on hydrolysis of sucrose ? (b) What are essential amino acids ?$
Carbohydrates
20 $Differentiate between the following : (i) Peptide linkage and Glycosidic linkage (ii) Essential amino acids and Non-essential amino acids$
Proteins
20 $How do you explain the following ? (a) Presence of an aldehyde group in glucose (b) Presence of a primary alcoholic group in glucose$
Carbohydrates
20 $(a) Write the hydrolysis products of lactose. (b) What are non-essential amino acids ?$
Carbohydrates
20 $Differentiate between the following : (i) Fibrous protein and Globular protein (ii) Peptide linkage and Phosphodiester linkage$
Proteins
20 $What are the hydrolysis products of the following ? (a) Lactose (b) DNA containing Thymine$
Carbohydrates
21 $How do you explain the following ? (a) Presence of a straight chain in glucose (b) Presence of five - OH groups in glucose which are attached to different carbon atoms$
Carbohydrates
21 $(a) Write any two fat soluble vitamins. (b) How will you confirm the presence of five - OH groups in a glucose molecule, which are attached to different carbon atoms ?$
Vitamins
21 $Differentiate between the following : (i) Acidic amino acids and basic amino acids (ii) Nucleotide and Nucleoside$
Proteins
21 $(a) Name two water-soluble vitamins. (b) How will you prove the absence of free - CHO group in the cyclic structure of glucose molecule ?$
Vitamins
21 $How do you explain the following ? (a) Presence of a carbonyl group in glucose (b) Presence of five - OH groups in glucose$
Carbohydrates
21 $(a) Name the disease caused by the deficiency of Vitamin A. (b) How will you confirm the presence of carbonyl group as an aldehydic group in glucose ?$
Vitamins
25 $Define the following terms : (a) Anomers (b) Invert sugar (c) Glycosidic linkage$
Carbohydrates
25 $\mathrm{Br_2}$
Carbohydrates
26 $How do you explain the presence of following in open structure of glucose ? (a) all the six carbon atoms are in a straight chain. (b) five -OH groups which are attached to different carbon atoms. (c) an aldehyde group.$
Carbohydrates
28 (A) $(a) Define the following terms : (i) Invert Sugar (ii) Polysaccharides (b) On the basis of structure differentiate between fibrous and globular proteins.$
Carbohydrates
28 (A) $Define the following term : (a) Reducing sugar (b) Differentiate between the following : (i) Fibrous proteins and globular proteins (ii) Nucleotide and nucleoside$
Carbohydrates
28 (A) $(a) Define the following terms : (i) Denaturation as related to proteins (ii) Oligosaccharides (b) On the basis of structure differentiate between Amylose and Amylopectin.$
Carbohydrates
28 (B) $(a) Why is glycogen known as animal starch ? (b) Differentiate between essential amino acids and non-essential amino acids. (c) What is the effect of denaturation on the structure of proteins ?$
Proteins
28 (B) $(a) What products would be formed when a nucleotide from DNA containing thymine is hydrolysed ? (b) How will you explain the presence of five -OH groups in glucose molecule which are attached to different carbon atoms ? (c) Write the reaction of glucose with HCN.$
Carbohydrates
28 (B) $\mathrm{H_2N-OH}$
Carbohydrates
Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc. Proteins and carbohydrates are essential constituents of our food. In addition, some simple molecules like vitamins and mineral salts also play an important role in the functions of organisms. All proteins are polymers of $\alpha$ -amino acids. Proteins can be classified into two types on the basis of their molecular shape — Fibrous and Globular proteins. Vitamins are accessory food factors required in the diet. They are classified as fat-soluble and water-soluble. Deficiency of vitamins leads to many diseases. Nucleic acids are the polymers of nucleotides which in turn consist of a base, a pentose sugar and phosphate moiety. There are two types of nucleic acids — DNA and RNA. Nucleic acids are responsible for the transfer of characters from parents to offsprings.
29 (a) $Write the name of basic building units of proteins and nucleic acids. How can you differentiate between Fibrous and Globular proteins on the basis of their structures ?$
Proteins
Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc. Proteins and carbohydrates are essential constituents of our food. In addition, some simple molecules like vitamins and mineral salts also play an important role in the functions of organisms. All proteins are polymers of $\alpha$ -amino acids. Proteins can be classified into two types on the basis of their molecular shape — Fibrous and Globular proteins. Vitamins are accessory food factors required in the diet. They are classified as fat-soluble and water-soluble. Deficiency of vitamins leads to many diseases. Nucleic acids are the polymers of nucleotides which in turn consist of a base, a pentose sugar and phosphate moiety. There are two types of nucleic acids — DNA and RNA. Nucleic acids are responsible for the transfer of characters from parents to offsprings.
29 (b) (i) $What products would be formed when a nucleotide from DNA containing thymine is hydrolyzed ?$
Nucleic Acids
Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc. Proteins and carbohydrates are essential constituents of our food. In addition, some simple molecules like vitamins and mineral salts also play an important role in the functions of organisms. All proteins are polymers of $\alpha$ -amino acids. Proteins can be classified into two types on the basis of their molecular shape — Fibrous and Globular proteins. Vitamins are accessory food factors required in the diet. They are classified as fat-soluble and water-soluble. Deficiency of vitamins leads to many diseases. Nucleic acids are the polymers of nucleotides which in turn consist of a base, a pentose sugar and phosphate moiety. There are two types of nucleic acids — DNA and RNA. Nucleic acids are responsible for the transfer of characters from parents to offsprings.
29 (b) (ii) $Write one structural difference between DNA and RNA.$
Nucleic Acids
Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc. Proteins and carbohydrates are essential constituents of our food. In addition, some simple molecules like vitamins and mineral salts also play an important role in the functions of organisms. All proteins are polymers of $\alpha$ -amino acids. Proteins can be classified into two types on the basis of their molecular shape — Fibrous and Globular proteins. Vitamins are accessory food factors required in the diet. They are classified as fat-soluble and water-soluble. Deficiency of vitamins leads to many diseases. Nucleic acids are the polymers of nucleotides which in turn consist of a base, a pentose sugar and phosphate moiety. There are two types of nucleic acids — DNA and RNA. Nucleic acids are responsible for the transfer of characters from parents to offsprings.
29 (c) $Give one example each of a fat-soluble vitamin and a water-soluble vitamin.$
Vitamins
Carbohydrates are optically active polyhydroxy aldehydes or ketones or the compounds which produce such units on hydrolysis. They have been broadly classified into three groups — monosaccharides, oligosaccharides and polysaccharides. The carbohydrates may also be classified as either reducing or non-reducing sugars. An important monosaccharide glucose is an aldohexose and is correctly named as D(+)–glucose. It was assigned the open structure on the basis of its reactions with HI, $\mathrm{NH_2OH}$ , $\mathrm{Br_2}$ water, $\mathrm{(CH_3CO)_2O}$ and nitric acid. Despite having the – CHO group, glucose does not give Schiff’s test and hydrogen sulphite addition product with $\mathrm{NaHSO_3}$ . It was found that glucose forms a six-membered ring in which one of the – OH groups add to the – CHO group and form a cyclic hemiacetal structure.
30 (a) $How do you explain the following ? (i) Presence of a carbonyl group in glucose (ii) Presence of five - OH groups in glucose which are attached to different carbon atoms.$
Carbohydrates
Carbohydrates are optically active polyhydroxy aldehydes or ketones or the compounds which produce such units on hydrolysis. They have been broadly classified into three groups — monosaccharides, oligosaccharides and polysaccharides. The carbohydrates may also be classified as either reducing or non-reducing sugars. An important monosaccharide glucose is an aldohexose and is correctly named as D(+)–glucose. It was assigned the open structure on the basis of its reactions with HI, $\mathrm{NH_2OH}$ , $\mathrm{Br_2}$ water, $\mathrm{(CH_3CO)_2O}$ and nitric acid. Despite having the – CHO group, glucose does not give Schiff’s test and hydrogen sulphite addition product with $\mathrm{NaHSO_3}$ . It was found that glucose forms a six-membered ring in which one of the – OH groups add to the – CHO group and form a cyclic hemiacetal structure.
30 (b) $What type of carbohydrates are called reducing sugars ?$
Carbohydrates
Carbohydrates are optically active polyhydroxy aldehydes or ketones or the compounds which produce such units on hydrolysis. They have been broadly classified into three groups — monosaccharides, oligosaccharides and polysaccharides. The carbohydrates may also be classified as either reducing or non-reducing sugars. An important monosaccharide glucose is an aldohexose and is correctly named as D(+)–glucose. It was assigned the open structure on the basis of its reactions with HI, $\mathrm{NH_2OH}$ , $\mathrm{Br_2}$ water, $\mathrm{(CH_3CO)_2O}$ and nitric acid. Despite having the – CHO group, glucose does not give Schiff’s test and hydrogen sulphite addition product with $\mathrm{NaHSO_3}$ . It was found that glucose forms a six-membered ring in which one of the – OH groups add to the – CHO group and form a cyclic hemiacetal structure.
30 (c) $In D(+)-glucose, what do the letter ‘D’ and sign ‘(+)’ represent ?$
Carbohydrates
Carbohydrates are optically active polyhydroxy aldehydes or ketones or the compounds which produce such units on hydrolysis. They have been broadly classified into three groups — monosaccharides, oligosaccharides and polysaccharides. The carbohydrates may also be classified as either reducing or non-reducing sugars. An important monosaccharide glucose is an aldohexose and is correctly named as D(+)–glucose. It was assigned the open structure on the basis of its reactions with HI, $\mathrm{NH_2OH}$ , $\mathrm{Br_2}$ water, $\mathrm{(CH_3CO)_2O}$ and nitric acid. Despite having the – CHO group, glucose does not give Schiff’s test and hydrogen sulphite addition product with $\mathrm{NaHSO_3}$ . It was found that glucose forms a six-membered ring in which one of the – OH groups add to the – CHO group and form a cyclic hemiacetal structure.
30 (c) OR $\alpha$
Carbohydrates

2025

45 q

4 $In the Haworth structure of the following carbohydrate, various carbon atoms have been numbered. The anomeric carbon is numbered as :$
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Carbohydrates
10 $Which of the following is/are examples of denaturation of protein ?$
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Proteins
11 $Nucleotides are joined together by$
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Nucleic Acids
11 $Which of the following statements is not true about glucose ?$
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Carbohydrates
12 $Pyranose ring of glucose is formed due to the reaction between :$
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Carbohydrates
12 $\alpha$
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Carbohydrates
12 $Scurvy is caused due to deficiency of$
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Vitamins
12 $\alpha$
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Proteins
12 $‘Scurvy’ is caused due to the deficiency of :$
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Vitamins
12 $\mathrm{B_1}$
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Vitamins
12 $Furanose ring of fructose is formed due to reaction between :$
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Carbohydrates
For questions number 13 to 16, two statements are given - one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below :
16 $\alpha$
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Proteins
For Questions number 13 to 16, two statements are given — one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.
16 $Assertion (A) : Vitamin C cannot be stored in our body. Reason (R) : Vitamin C is water soluble and excreted in urine.$
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Vitamins
For Questions number 13 to 16, two statements are given — one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.
16 $Assertion (A) : Maltose is a reducing sugar. Reason (R) : One of the two glucose units can open to expose free aldehydic group in solution.$
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Carbohydrates
For question number 13 to 16, two statements are given - one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below :
16 $Assertion (A) : Vitamin D cannot be stored in our body. Reason (R) : Vitamin D is fat soluble vitamin and is not excreted from the body in urine.$
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Vitamins
For Questions number 13 to 16, two statements are given — one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.
16 $Assertion (A) : Vitamin K can be stored in our body. Reason (R) : Vitamin K is a water soluble vitamin.$
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Vitamins
20 $Write two differences between Amylose and Amylopectin components of starch.$
Carbohydrates
21 $How do you explain the following ? (a) Presence of an aldehydic group in glucose. (b) Presence of five - OH groups in glucose.$
Carbohydrates
21 $\mathrm{Br_2}$
Carbohydrates
21 $What is meant by essential amino acids ? Why are amino acids amphoteric in nature ?$
Proteins
21 $What are the hydrolysis products of : (a) Sucrose (b) Lactose$
Carbohydrates
21 $\alpha$
Proteins
21 $The two strands in DNA are not identical but complementary. Explain. What products would be formed when DNA is hydrolysed ?$
Nucleic Acids
22 $Differentiate between : (a) Essential amino acids and Non-essential amino acids (b) Peptide linkage and Glycosidic linkage (c) Fibrous protein and Globular protein$
Proteins
28 $\mathrm{NH_2OH}$
Carbohydrates
28 $Define the following terms : (a) Native protein (b) Nucleotide (c) Essential amino acid$
Proteins
28 $\mathrm{Br_2}$
Carbohydrates
28 $(a) Name the vitamin which is responsible for coagulation of blood. (b) What is meant by denaturation of protein ? Give an example.$
Proteins
28 $(a) What is the difference between native protein and denatured protein ? (b) Which one of the following is a disaccharide ? Glucose, Lactose, Amylose, Fructose (c) Which vitamin is responsible for the coagulation of blood ?$
Proteins
28 $\mathrm{H_2N-OH}$
Carbohydrates
28 $\alpha$
Nucleic Acids
28 $Define the following terms : (a) Glycosidic linkage (b) Invert sugar (c) Oligosaccharides$
Carbohydrates
28 $(a) Name the vitamin whose deficiency causes pernicious anaemia. (b) Write any two differences between globular and fibrous proteins.$
Proteins
Carbohydrates are polyhydroxy aldehydes or ketones that represent enormous structural diversity in terms of the arrangement of atoms in space, resulting in hundreds of stereoisomers. Although the chemical properties of most stereoisomers may not be very different, their metabolic rate and utilization in biological systems is significantly different and known to influence the overall carbohydrate metabolism. Structural variants, which arise due to a different arrangement of atoms in three-dimensional space are known as stereoisomers. The number of stereoisomers can be theoretically estimated by using the formula 2n, where 'n' is the number of stereocenters or asymmetric (chiral) carbon atoms in a molecule. Out of these stereoisomers, there are some structures, which are mirror images of each other, and they are referred to as enantiomers.
29 (a) $Give chemical reactions to show the presence of an aldehydic group and straight chain in glucose.$
Carbohydrates
Carbohydrates are polyhydroxy aldehydes or ketones that represent enormous structural diversity in terms of the arrangement of atoms in space, resulting in hundreds of stereoisomers. Although the chemical properties of most stereoisomers may not be very different, their metabolic rate and utilization in biological systems is significantly different and known to influence the overall carbohydrate metabolism. Structural variants, which arise due to a different arrangement of atoms in three-dimensional space are known as stereoisomers. The number of stereoisomers can be theoretically estimated by using the formula 2n, where 'n' is the number of stereocenters or asymmetric (chiral) carbon atoms in a molecule. Out of these stereoisomers, there are some structures, which are mirror images of each other, and they are referred to as enantiomers.
29 (b) (i) $Define anomers.$
Carbohydrates
Carbohydrates are polyhydroxy aldehydes or ketones that represent enormous structural diversity in terms of the arrangement of atoms in space, resulting in hundreds of stereoisomers. Although the chemical properties of most stereoisomers may not be very different, their metabolic rate and utilization in biological systems is significantly different and known to influence the overall carbohydrate metabolism. Structural variants, which arise due to a different arrangement of atoms in three-dimensional space are known as stereoisomers. The number of stereoisomers can be theoretically estimated by using the formula 2n, where 'n' is the number of stereocenters or asymmetric (chiral) carbon atoms in a molecule. Out of these stereoisomers, there are some structures, which are mirror images of each other, and they are referred to as enantiomers.
29 (b) (ii) OR $\beta$
Carbohydrates
Carbohydrates are polyhydroxy aldehydes or ketones that represent enormous structural diversity in terms of the arrangement of atoms in space, resulting in hundreds of stereoisomers. Although the chemical properties of most stereoisomers may not be very different, their metabolic rate and utilization in biological systems is significantly different and known to influence the overall carbohydrate metabolism. Structural variants, which arise due to a different arrangement of atoms in three-dimensional space are known as stereoisomers. The number of stereoisomers can be theoretically estimated by using the formula 2n, where 'n' is the number of stereocenters or asymmetric (chiral) carbon atoms in a molecule. Out of these stereoisomers, there are some structures, which are mirror images of each other, and they are referred to as enantiomers.
29 (c) $Sucrose is known as invert sugar. Explain.$
Carbohydrates
The $\alpha$ -amino acids are the building blocks of proteins. All $\alpha$ -amino acids exist as zwitter ion due to which they show amphoteric behaviour. All amino acids are joined through peptide bond. Proteins are broadly classified as globular proteins and fibrous proteins. Globular proteins are water soluble, whereas fibrous proteins are not. The complete structure of protein is discussed at four different levels i.e. primary, secondary, tertiary and quaternary structures. Protein loses its biological activity in denatured form.
30 (a) $Define the following : (i) Peptide linkage (ii) Denatured protein$
Proteins
Ribose and 2-deoxyribose have an important role in biology. Among the most important derivatives are those with phosphate groups attached at the 5 position. Mono-, di- and tri-phosphate forms are important, as well as 3-5 cyclic monophosphates. Purines and pyrimidines form an important class of compounds with ribose and deoxyribose. When these purine and pyrimidine derivatives are coupled to a ribose sugar, they are called nucleosides.
30 (a) $What products would be formed when DNA is hydrolysed ? How is DNA different from RNA with reference to a structure ?$
Nucleic Acids
The $\alpha$ -amino acids are the building blocks of proteins. All $\alpha$ -amino acids exist as zwitter ion due to which they show amphoteric behaviour. All amino acids are joined through peptide bond. Proteins are broadly classified as globular proteins and fibrous proteins. Globular proteins are water soluble, whereas fibrous proteins are not. The complete structure of protein is discussed at four different levels i.e. primary, secondary, tertiary and quaternary structures. Protein loses its biological activity in denatured form.
30 (b) $Why do amino acids show amphoteric behaviour ?$
Proteins
Ribose and 2-deoxyribose have an important role in biology. Among the most important derivatives are those with phosphate groups attached at the 5 position. Mono-, di- and tri-phosphate forms are important, as well as 3-5 cyclic monophosphates. Purines and pyrimidines form an important class of compounds with ribose and deoxyribose. When these purine and pyrimidine derivatives are coupled to a ribose sugar, they are called nucleosides.
30 (b) $Differentiate between nucleotide and nucleoside.$
Nucleic Acids
The $\alpha$ -amino acids are the building blocks of proteins. All $\alpha$ -amino acids exist as zwitter ion due to which they show amphoteric behaviour. All amino acids are joined through peptide bond. Proteins are broadly classified as globular proteins and fibrous proteins. Globular proteins are water soluble, whereas fibrous proteins are not. The complete structure of protein is discussed at four different levels i.e. primary, secondary, tertiary and quaternary structures. Protein loses its biological activity in denatured form.
30 (c) (i) $How can you differentiate between Fibrous protein and Globular protein ?$
Proteins
Ribose and 2-deoxyribose have an important role in biology. Among the most important derivatives are those with phosphate groups attached at the 5 position. Mono-, di- and tri-phosphate forms are important, as well as 3-5 cyclic monophosphates. Purines and pyrimidines form an important class of compounds with ribose and deoxyribose. When these purine and pyrimidine derivatives are coupled to a ribose sugar, they are called nucleosides.
30 (c) (i) $Mention two important functions of nucleic acid.$
Nucleic Acids
Ribose and 2-deoxyribose have an important role in biology. Among the most important derivatives are those with phosphate groups attached at the 5 position. Mono-, di- and tri-phosphate forms are important, as well as 3-5 cyclic monophosphates. Purines and pyrimidines form an important class of compounds with ribose and deoxyribose. When these purine and pyrimidine derivatives are coupled to a ribose sugar, they are called nucleosides.
30 (c) (ii) $Name the linkage which joins two nucleotides. Name the base that is found in nucleotide of RNA but not in DNA.$
Nucleic Acids
The $\alpha$ -amino acids are the building blocks of proteins. All $\alpha$ -amino acids exist as zwitter ion due to which they show amphoteric behaviour. All amino acids are joined through peptide bond. Proteins are broadly classified as globular proteins and fibrous proteins. Globular proteins are water soluble, whereas fibrous proteins are not. The complete structure of protein is discussed at four different levels i.e. primary, secondary, tertiary and quaternary structures. Protein loses its biological activity in denatured form.
30 (c) (ii) $Write the names of two different secondary structures of proteins.$
Proteins

2024

47 q

1 $The specific sequence in which amino acids are arranged in a protein is called its$
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Proteins
3 $Maltose is made up of :$
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Carbohydrates
3 $Which of the following acids represents Vitamin C ?$
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Vitamins
3 $\beta$
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Nucleic Acids
3 $Nucleotides are composed of a :$
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Nucleic Acids
8 $'Scurvy' is caused by the deficiency of vitamin :$
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Vitamins
9 $The vitamin which plays an important role in coagulating blood is :$
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Vitamins
9 $‘Night-Blindness’ is caused by the deficiency of Vitamin :$
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Vitamins
12 $Which functional groups of glucose interact to form cyclic hemiacetal leading to pyranose structure ?$
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Carbohydrates
12 $All proteins on hydrolysis give :$
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Proteins
12 $The specific sequence in which amino acids are arranged in a protein is called :$
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Proteins
For Questions number 13 to 16, two statements are given — one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.
14 $Assertion (A) : Uracil base is present in DNA. Reason (R) : DNA undergoes self-replication.$
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Nucleic Acids
For Questions number 13 to 16, two statements are given — one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.
14 $Assertion (A) : Vitamin C cannot be stored in our body. Reason (R) : Vitamin C is water soluble and readily excreted in urine.$
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Vitamins
For Questions number 13 to 16, two statements are given — one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.
14 $Assertion (A) : Uracil base is present in RNA. Reason (R) : RNA undergoes self-replication.$
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Nucleic Acids
For questions number 13 to 16, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below :
15 $Assertion (A) : Fructose is a reducing sugar. Reason (R) : Fructose does not reduce Fehling solution and Tollen's reagent.$
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Carbohydrates
17 $\mathrm{(CH_3CO)_2O}$
Carbohydrates
17 $\mathrm{H_2N-OH}$
Carbohydrates
17 $Define the following terms : (a) Essential amino acids (b) Nucleotide$
Proteins
17 $\mathrm{H_2N-OH}$
Carbohydrates
18 $Classify the following sugars into monosaccharides and disaccharides : Galactose, Glucose, Lactose and Maltose$
Carbohydrates
19 $\mathrm{HNO_3}$
Carbohydrates
18 $\mathrm{Br_2}$
Carbohydrates
19 $Define the following terms : (a) Peptide linkage (b) Essential amino acids$
Proteins
19 $Classify the following sugars into monosaccharides and disaccharides : Sucrose, Lactose, Glucose, Fructose$
Carbohydrates
21 $\mathrm{HNO_3}$
Carbohydrates
21 $(a) What happens when Glucose reacts with HI ? Write chemical equation. (b) Which type of bond holds a DNA double helix together ?$
Carbohydrates
21 $Define the following terms : (a) Denaturation of protein (b) Invert sugar$
Proteins
21 $(a) What happens when glucose reacts with bromine water ? Write chemical equation. (b) Two bases are mentioned below, identify which is present in DNA and which one is present in RNA : (i) Thymine, (ii) Uracil.$
Carbohydrates
21 $Classify the following sugars into monosaccharides and disaccharides : Fructose, Lactose, Glucose, Maltose$
Carbohydrates
21 $(a) What happens when Glucose reacts with Nitric acid ? Write chemical equation. (b) Write one structural difference between DNA and RNA.$
Carbohydrates
26 $Explain the following terms : (a) Essential amino acids (b) Peptide bond (c) Denaturation$
Proteins
26 $Define the following terms : (a) Glycosidic linkage (b) Primary structure of protein (c) Disaccharides$
Carbohydrates
26 $Define the following terms : (a) Non essential amino acids. (b) Monosaccharides (c) Anomers$
Carbohydrates
27 $Answer the following : (any three) (a) What is peptide linkage ? (b) What type of bonds hold a DNA double helix together ? (c) Which one of the following is a polysaccharide ? Sucrose, Glucose, Starch, Fructose (d) Give one example each for water-soluble vitamins and fat-soluble vitamins.$
Proteins
Carbohydrates are essential for life in both plants and animals. Carbohydrates are used as storage molecules as starch in plants and glycogen in animals. Chemically they are polyhydroxy aldehydes or ketones. On the basis of their behaviour on hydrolysis, carbohydrates are classified as monosaccharides, oligosaccharides and polysaccharides. All monosaccharides are reducing sugars, i.e., they are oxidized by Tollens' reagent and Fehling's solution. A monosaccharide like glucose is aldohexose and its molecular formula was found to be $\mathrm{C_6H_{12}O_6}$ . After reacting with different reagents like HI, $\mathrm{H_2N - OH}$ , Bromine water, $\mathrm{(CH_3CO)_2O}$ , etc. its structure was found to contain one aldehyde group, one primary alcoholic group, $(-\mathrm{CH_2OH})$ and four secondary alcoholic groups $(>\mathrm{CHOH})$ . Despite having the aldehyde group, glucose does not give some of the reactions of aldehyde group like Schiff's test, $\mathrm{NaHSO_3}$ addition. This explains the existence of glucose in two cyclic hemiacetal forms which differ only in the configuration of the hydroxyl group at C $-$ 1.
29 (a) $What are reducing sugars ?$
Carbohydrates
Carbohydrates are essential for life in both plants and animals. Carbohydrates are used as storage molecules as starch in plants and glycogen in animals. Chemically they are polyhydroxy aldehydes or ketones. On the basis of their behaviour on hydrolysis, carbohydrates are classified as monosaccharides, oligosaccharides and polysaccharides. All monosaccharides are reducing sugars, i.e., they are oxidized by Tollens' reagent and Fehling's solution. A monosaccharide like glucose is aldohexose and its molecular formula was found to be $\mathrm{C_6H_{12}O_6}$ . After reacting with different reagents like HI, $\mathrm{H_2N - OH}$ , Bromine water, $\mathrm{(CH_3CO)_2O}$ , etc. its structure was found to contain one aldehyde group, one primary alcoholic group, $(-\mathrm{CH_2OH})$ and four secondary alcoholic groups $(>\mathrm{CHOH})$ . Despite having the aldehyde group, glucose does not give some of the reactions of aldehyde group like Schiff's test, $\mathrm{NaHSO_3}$ addition. This explains the existence of glucose in two cyclic hemiacetal forms which differ only in the configuration of the hydroxyl group at C $-$ 1.
29 (b) $Classify the following into monosaccharide and disaccharide : Fructose, Sucrose, Lactose, Galactose$
Carbohydrates
Carbohydrates are essential for life in both plants and animals. Carbohydrates are used as storage molecules as starch in plants and glycogen in animals. Chemically they are polyhydroxy aldehydes or ketones. On the basis of their behaviour on hydrolysis, carbohydrates are classified as monosaccharides, oligosaccharides and polysaccharides. All monosaccharides are reducing sugars, i.e., they are oxidized by Tollens' reagent and Fehling's solution. A monosaccharide like glucose is aldohexose and its molecular formula was found to be $\mathrm{C_6H_{12}O_6}$ . After reacting with different reagents like HI, $\mathrm{H_2N - OH}$ , Bromine water, $\mathrm{(CH_3CO)_2O}$ , etc. its structure was found to contain one aldehyde group, one primary alcoholic group, $(-\mathrm{CH_2OH})$ and four secondary alcoholic groups $(>\mathrm{CHOH})$ . Despite having the aldehyde group, glucose does not give some of the reactions of aldehyde group like Schiff's test, $\mathrm{NaHSO_3}$ addition. This explains the existence of glucose in two cyclic hemiacetal forms which differ only in the configuration of the hydroxyl group at C $-$ 1.
29 (c) $Name the polysaccharide which is known as 'animal starch'. Why is it called 'animal starch' ?$
Carbohydrates
Carbohydrates are essential for life in both plants and animals. Carbohydrates are used as storage molecules as starch in plants and glycogen in animals. Chemically they are polyhydroxy aldehydes or ketones. On the basis of their behaviour on hydrolysis, carbohydrates are classified as monosaccharides, oligosaccharides and polysaccharides. All monosaccharides are reducing sugars, i.e., they are oxidized by Tollens' reagent and Fehling's solution. A monosaccharide like glucose is aldohexose and its molecular formula was found to be $\mathrm{C_6H_{12}O_6}$ . After reacting with different reagents like HI, $\mathrm{H_2N - OH}$ , Bromine water, $\mathrm{(CH_3CO)_2O}$ , etc. its structure was found to contain one aldehyde group, one primary alcoholic group, $(-\mathrm{CH_2OH})$ and four secondary alcoholic groups $(>\mathrm{CHOH})$ . Despite having the aldehyde group, glucose does not give some of the reactions of aldehyde group like Schiff's test, $\mathrm{NaHSO_3}$ addition. This explains the existence of glucose in two cyclic hemiacetal forms which differ only in the configuration of the hydroxyl group at C $-$ 1.
29 (c) OR $-\mathrm{OH}$
Carbohydrates
Certain organic compounds are required in small amounts in our diet but their deficiency causes specific disease. These compounds are called vitamins. Most of the vitamins cannot be synthesized in our body but plants can synthesize almost all of them. So they are considered as essential food factors. However, the bacteria of the gut can produce some of the vitamins required by us. All the vitamins are generally available in our diet. The term ‘vitamin’ was coined from the words vital + amine, since the earlier identified compounds had amino group. Vitamins are classified into two groups depending upon their solubility in water or fat namely-fat soluble vitamins and water soluble vitamins.
30 (a) $\mathrm{B_6}$
Vitamins
Proteins are the most abundant biomolecules of the living system. Proteins are the polymers of about twenty different $\alpha$ -amino acids which are linked by peptide bonds. Ten amino acids are called essential amino acids. In zwitter ionic form, amino acids show amphoteric behaviour as they react both with acids and bases. On the basis of their molecular shape, proteins are classified into two types : Fibrous and Globular proteins. Structure and shape of proteins can be studied at four different levels i.e., primary, secondary, tertiary and quaternary, each level being more complex than the previous one. The secondary or tertiary structure of proteins get disturbed on change of pH or temperature and they are not able to perform their functions. This is called denaturation of proteins.
30 (a) $What are essential amino acids ?$
Proteins
Certain organic compounds are required in small amounts in our diet but their deficiency causes specific disease. These compounds are called vitamins. Most of the vitamins cannot be synthesized in our body but plants can synthesize almost all of them. So they are considered as essential food factors. However, the bacteria of the gut can produce some of the vitamins required by us. All the vitamins are generally available in our diet. The term ‘vitamin’ was coined from the words vital + amine, since the earlier identified compounds had amino group. Vitamins are classified into two groups depending upon their solubility in water or fat namely-fat soluble vitamins and water soluble vitamins.
30 (a) $\mathrm{B_6}$
Vitamins
Proteins are the most abundant biomolecules of the living system. Proteins are the polymers of about twenty different $\alpha$ -amino acids which are linked by peptide bonds. Ten amino acids are called essential amino acids. In zwitter ionic form, amino acids show amphoteric behaviour as they react both with acids and bases. On the basis of their molecular shape, proteins are classified into two types : Fibrous and Globular proteins. Structure and shape of proteins can be studied at four different levels i.e., primary, secondary, tertiary and quaternary, each level being more complex than the previous one. The secondary or tertiary structure of proteins get disturbed on change of pH or temperature and they are not able to perform their functions. This is called denaturation of proteins.
30 (b) $What is meant by zwitter ionic form of amino acids ?$
Proteins
Certain organic compounds are required in small amounts in our diet but their deficiency causes specific disease. These compounds are called vitamins. Most of the vitamins cannot be synthesized in our body but plants can synthesize almost all of them. So they are considered as essential food factors. However, the bacteria of the gut can produce some of the vitamins required by us. All the vitamins are generally available in our diet. The term ‘vitamin’ was coined from the words vital + amine, since the earlier identified compounds had amino group. Vitamins are classified into two groups depending upon their solubility in water or fat namely-fat soluble vitamins and water soluble vitamins.
30 (b) $Name the vitamin whose deficiency causes increased blood clotting time.$
Vitamins
Certain organic compounds are required in small amounts in our diet but their deficiency causes specific disease. These compounds are called vitamins. Most of the vitamins cannot be synthesized in our body but plants can synthesize almost all of them. So they are considered as essential food factors. However, the bacteria of the gut can produce some of the vitamins required by us. All the vitamins are generally available in our diet. The term ‘vitamin’ was coined from the words vital + amine, since the earlier identified compounds had amino group. Vitamins are classified into two groups depending upon their solubility in water or fat namely-fat soluble vitamins and water soluble vitamins.
30 (c) $Xerophthalmia is caused by the deficiency of which vitamin ? Give two sources of this vitamin.$
Vitamins
Proteins are the most abundant biomolecules of the living system. Proteins are the polymers of about twenty different $\alpha$ -amino acids which are linked by peptide bonds. Ten amino acids are called essential amino acids. In zwitter ionic form, amino acids show amphoteric behaviour as they react both with acids and bases. On the basis of their molecular shape, proteins are classified into two types : Fibrous and Globular proteins. Structure and shape of proteins can be studied at four different levels i.e., primary, secondary, tertiary and quaternary, each level being more complex than the previous one. The secondary or tertiary structure of proteins get disturbed on change of pH or temperature and they are not able to perform their functions. This is called denaturation of proteins.
30 (c) $(i) Give one example each for Fibrous protein and Globular protein. (ii) What type of linkages hold monomers of proteins together ?$
Proteins
Certain organic compounds are required in small amounts in our diet but their deficiency causes specific disease. These compounds are called vitamins. Most of the vitamins cannot be synthesized in our body but plants can synthesize almost all of them. So they are considered as essential food factors. However, the bacteria of the gut can produce some of the vitamins required by us. All the vitamins are generally available in our diet. The term ‘vitamin’ was coined from the words vital + amine, since the earlier identified compounds had amino group. Vitamins are classified into two groups depending upon their solubility in water or fat namely-fat soluble vitamins and water soluble vitamins.
30 (c) OR $Why can’t vitamin C be stored in our body ? Name the disease caused by the deficiency of this vitamin.$
Vitamins
Proteins are the most abundant biomolecules of the living system. Proteins are the polymers of about twenty different $\alpha$ -amino acids which are linked by peptide bonds. Ten amino acids are called essential amino acids. In zwitter ionic form, amino acids show amphoteric behaviour as they react both with acids and bases. On the basis of their molecular shape, proteins are classified into two types : Fibrous and Globular proteins. Structure and shape of proteins can be studied at four different levels i.e., primary, secondary, tertiary and quaternary, each level being more complex than the previous one. The secondary or tertiary structure of proteins get disturbed on change of pH or temperature and they are not able to perform their functions. This is called denaturation of proteins.
30 (c) OR $(i) What is the structural feature which characterises a reducing sugar ? (ii) What is the structural difference between nucleoside and nucleotide ?$
Carbohydrates

2023

47 q

3 $\alpha$
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Carbohydrates
5 $On hydrolysis, which of the following carbohydrates gives only glucose ?$
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Carbohydrates
5 $Proteins are polymers of$
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Proteins
5 $When D-glucose reacts with HI, it forms$
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Carbohydrates
5 $\alpha$
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Proteins
5 $Helical structure of proteins is stabilized by :$
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Proteins
6 $A vitamin which plays a vital role in the clotting of blood is :$
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Vitamins
6 $Which of the following vitamins is water soluble ?$
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Vitamins
7 $In the ring structure of glucose, the anomeric carbon is :$
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Carbohydrates
8 $Deficiency of Vitamin B causes :$
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Vitamins
10 $Which of the following statements is not true about glucose ?$
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Carbohydrates
10 $Hydrolysis of sucrose is called$
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Carbohydrates
10 $\beta$
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Proteins
11 $On hydrolysis, which of the following carbohydrates gives only glucose ?$
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Carbohydrates
11 $On hydrolysis, which of the following carbohydrates gives glucose and fructose ?$
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Carbohydrates
11 $On hydrolysis, which of the following carbohydrates gives glucose and galactose ?$
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Carbohydrates
12 $The deficiency of which of the following vitamins causes 'Rickets' ?$
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Vitamins
12 $Deficiency of which of the following vitamins causes Pernicious anaemia ?$
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Vitamins
12 $The deficiency of which of the following vitamins causes Scurvy ?$
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Vitamins
13 $The glycosidic linkage involved in linking the glucose units in amylase part of starch is :$
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Carbohydrates
14 $Which of the following is a non-reducing sugar ?$
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Carbohydrates
14 $\alpha$
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Proteins
For questions number 15 to 18, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below :
15 $\alpha$
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Proteins
For questions number 15 to 18, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below :
15 $Assertion (A) : Vitamin C cannot be stored in our body. Reason (R) : Vitamin C is fat soluble and is excreted from the body in urine.$
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Vitamins
For questions number 15 to 18, two statements are given – one labelled as Assertion (A) and the other labelled as Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below :
15 $Assertion (A) : The backbone of DNA and RNA molecules is a chain consisting of heterocyclic base, pentose sugar and phosphate group. Reason (R) : Nucleotides and nucleosides mainly differ from each other in presence of phosphate group.$
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Nucleic Acids
19 $What are nucleic acids ? Why two strands in DNA are not identical but are complementary ?$
Nucleic Acids
22 (a) $(i) How are carbohydrates stored in animal body ? Mention any one organ where they are present. (ii) What is the basic structural difference between starch and cellulose ?$
Carbohydrates
22 (b) $Differentiate between : (i) Peptide linkage and Glycosidic linkage (ii) Nucleoside and Nucleotide$
Nucleic Acids
23 $(a) What is the difference between a nucleoside and nucleotide ? (b) What products would be formed when a nucleotide from DNA containing thymine is hydrolysed ?$
Nucleic Acids
25 $Give the reaction of glucose with hydrogen cyanide. Presence of which group is confirmed by this reaction ?$
Carbohydrates
25 $Give the reaction of heating glucose with hydroxylamine. Presence of which group is confirmed by this reaction ?$
Carbohydrates
25 $(a) Write chemical reaction to show that open structure of D-glucose contains the straight chain. (b) What type of linkage is responsible for the formation of protein ?$
Carbohydrates
25 $Give the reaction of glucose with acetic anhydride. Presence of which group is confirmed by this reaction ?$
Carbohydrates
25 $Write two differences between DNA and RNA.$
Nucleic Acids
25 $Define denaturation of protein. What is the effect of denaturation on the structure of protein ?$
Proteins
29 $Give reasons for any 3 of the following observations : (a) Penta-acetate of glucose does not react with hydroxylamine. (b) Amino acids behave like salts. (c) Water soluble vitamins must be taken regularly in diet. (d) The two strands in DNA are complimentary to each other.$
Carbohydrates
30 $\mathrm{HNO_3}$
Proteins
30 $\mathrm{HI}$
Carbohydrates
30 $(a) What are the hydrolysis products of (i) Lactose, (ii) Maltose ? (b) Give the basic structural difference between starch and cellulose.$
Carbohydrates
Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc. Carbohydrates are optically active polyhydroxy aldehydes or ketones or molecules which provide such units on hydrolysis. They are broadly classified into three groups — monosaccharides, oligosaccharides and polysaccharides. Monosaccharides are held together by glycosidic linkages to form disaccharides like sucrose, maltose or polysaccharides like starch and cellulose. Another biomolecule : proteins are polymers of $\alpha$ -amino acids which are linked by peptide bonds. Ten amino acids are called essential amino acids. Structure and shape of proteins can be studied at four different levels i.e. primary, secondary, tertiary and quaternary, each level being more complex than the previous one.
31 (i) $What is the difference between a glycosidic linkage and peptide linkage ?$
Proteins
Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc. Carbohydrates are optically active polyhydroxy aldehydes or ketones or molecules which provide such units on hydrolysis. They are broadly classified into three groups — monosaccharides, oligosaccharides and polysaccharides. Monosaccharides are held together by glycosidic linkages to form disaccharides like sucrose, maltose or polysaccharides like starch and cellulose. Another biomolecule : proteins are polymers of $\alpha$ -amino acids which are linked by peptide bonds. Ten amino acids are called essential amino acids. Structure and shape of proteins can be studied at four different levels i.e. primary, secondary, tertiary and quaternary, each level being more complex than the previous one.
31 (ii) $Which amino acids are called essential amino acids ?$
Proteins
Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc. Carbohydrates are optically active polyhydroxy aldehydes or ketones or molecules which provide such units on hydrolysis. They are broadly classified into three groups — monosaccharides, oligosaccharides and polysaccharides. Monosaccharides are held together by glycosidic linkages to form disaccharides like sucrose, maltose or polysaccharides like starch and cellulose. Another biomolecule : proteins are polymers of $\alpha$ -amino acids which are linked by peptide bonds. Ten amino acids are called essential amino acids. Structure and shape of proteins can be studied at four different levels i.e. primary, secondary, tertiary and quaternary, each level being more complex than the previous one.
31 (iii) (a) $What are the common types of secondary structures of proteins ? Write any two forces which stabilise the secondary and tertiary structures of protein.$
Proteins
Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc. Carbohydrates are optically active polyhydroxy aldehydes or ketones or molecules which provide such units on hydrolysis. They are broadly classified into three groups — monosaccharides, oligosaccharides and polysaccharides. Monosaccharides are held together by glycosidic linkages to form disaccharides like sucrose, maltose or polysaccharides like starch and cellulose. Another biomolecule : proteins are polymers of $\alpha$ -amino acids which are linked by peptide bonds. Ten amino acids are called essential amino acids. Structure and shape of proteins can be studied at four different levels i.e. primary, secondary, tertiary and quaternary, each level being more complex than the previous one.
31 (iii) (b) $Define denaturation of protein with an example. During denaturation which structures of protein lose their biological activity ?$
Proteins
Carbohydrates are optically active polyhydroxy aldehydes and ketones. They are also called saccharides. All those carbohydrates which reduce Fehling's solution and Tollen's reagent are referred to as reducing sugars. Glucose, the most important source of energy for mammals, is obtained by the hydrolysis of starch. Vitamins are accessory food factors required in the diet. Proteins are the polymers of $\alpha$ -amino acids and perform various structural and dynamic functions in the organisms. Deficiency of vitamins leads to many diseases.
32 (a) $The penta-acetate of glucose does not react with Hydroxylamine. What does it indicate ?$
Carbohydrates
Carbohydrates are optically active polyhydroxy aldehydes and ketones. They are also called saccharides. All those carbohydrates which reduce Fehling's solution and Tollen's reagent are referred to as reducing sugars. Glucose, the most important source of energy for mammals, is obtained by the hydrolysis of starch. Vitamins are accessory food factors required in the diet. Proteins are the polymers of $\alpha$ -amino acids and perform various structural and dynamic functions in the organisms. Deficiency of vitamins leads to many diseases.
32 (b) $Why cannot vitamin C be stored in our body ?$
Vitamins
Carbohydrates are optically active polyhydroxy aldehydes and ketones. They are also called saccharides. All those carbohydrates which reduce Fehling's solution and Tollen's reagent are referred to as reducing sugars. Glucose, the most important source of energy for mammals, is obtained by the hydrolysis of starch. Vitamins are accessory food factors required in the diet. Proteins are the polymers of $\alpha$ -amino acids and perform various structural and dynamic functions in the organisms. Deficiency of vitamins leads to many diseases.
32 (c) $Define the following as related to proteins : (i) Peptide linkage (ii) Denaturation$
Proteins
Carbohydrates are optically active polyhydroxy aldehydes and ketones. They are also called saccharides. All those carbohydrates which reduce Fehling's solution and Tollen's reagent are referred to as reducing sugars. Glucose, the most important source of energy for mammals, is obtained by the hydrolysis of starch. Vitamins are accessory food factors required in the diet. Proteins are the polymers of $\alpha$ -amino acids and perform various structural and dynamic functions in the organisms. Deficiency of vitamins leads to many diseases.
32 (c) $Define the following as related to carbohydrates : (i) Anomers (ii) Glycosidic linkage$
Carbohydrates

The 10 board questions to practise first

The questions the board asked again come first, most asked first. Each one says how often and when.

Question 1
Asked 3 times: 2023, 2024, 2025
12 $Scurvy is caused due to deficiency of$
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Question 2
Asked 3 times: 2023*, 2024, 2025 (* = numbers or wording changed that year)
Two statements are given, one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer from the options given below.
16 $Assertion (A) : Vitamin C cannot be stored in our body. Reason (R) : Vitamin C is water soluble and excreted in urine.$
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Question 3
Asked 2 times: 2024, 2026
10 $Each polypeptide in a protein has amino acids linked with each other in a specific sequence and it is this sequence of amino acids that is said to be :$
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Question 4
Asked 2 times: 2023, 2026
11 $On hydrolysis, which of the following carbohydrates gives only glucose ?$
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Question 5
Asked 2 times: 2023, 2026
11 $An example of non-reducing sugar is$
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Question 6
Asked 2 times: 2025*, 2026 (* = numbers or wording changed that year)
21 $How do you explain the following ? (a) Presence of a carbonyl group in glucose (b) Presence of five - OH groups in glucose$
Question 7
Asked 2 times: 2023*, 2026 (* = numbers or wording changed that year)
12 $Which of the following is a water-soluble vitamin ?$
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Question 8
Asked 2 times: 2023*, 2025 (* = numbers or wording changed that year)
11 $Which of the following statements is not true about glucose ?$
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Question 9
Asked 2 times: 2024, 2025
12 $Pyranose ring of glucose is formed due to the reaction between :$
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Question 10
Asked 2 times: 2024, 2025
21 $\mathrm{Br_2}$

Intext Questions

Exercises

What the board has asked from this chapter

2026

2025

2024

2023

The 10 board questions to practise first

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10