BIO-MOLECULES

2025
1. Which of the following is/are examples of denaturation of protein ?
(a) Coagulation of egg white (b) Curdling of milk
(c) Clotting of blood (d) Both (A) and ( B)
2. Nucleotides are joined together by
(a) Glycosidic linkage (b) peptide linkage
(c) Hydrogen bond (d) Phosphodiester linkage
3. Scurvy is caused due to deficiency of
(a) Vitamin B1 (b) Vitamin B2
(c) Ascorbic acid (d) Glutamic acid
4. Assertion (A) : Vitamin D cannot be stored in our body.
Reason (R) : Vitamin D is fat soluble and is not excreted from body in urine.
5. Define the following terms :
(a) Glycosidic linkage (b) Invert sugar (c) Oligosaccharides
2024
1. Which of the following acids represents Vitamin C ?
(a) Saccharic acid (b) Gluconic acid (c) Ascorbic acid (d) Benzoic acid
2. (a) What happens when glucose reacts with HI, HNO3, Br2 ? Write chemical equation.
(b) Whicyh type of bond holds a DNA double helix together ?
(c) Write one structural difference between DNA & RNA .
3. Define the following terms :
(a) Non – essential amino – acids (b) Monosaccharides (c) Anomers (d) Glycosidic linkage
(e) Primary structure of protein (f) Disaccharides
2023
1. Hydrolysis of sucrose is called
(a) inversion (b) hydration (c) esterification (d) saponification
2. Assertion : proteins are polymers of α- amino acids connected by peptide bond.
Reason : A tetrapeptide contains 4 amino acids linked by 4 peptide bonds.
3. Draw the Zwitter ion structure of sulphonic acid.
4. Give the reaction of glucose with hydrogen cyanide. Presence of which group is confirmed by this reaction ?
5. Give reasons for the following observations :
(a) penta-acetate of glucose does not reacts with hydroxylamine ?
(b) Amino acids behaves like salt ?
(c) Water soluble vitamins must be taken regularly in diet ?
(d) The two strands in DNA are complimentary to each other ?
6. β- Pleated structure in proteins refers to
(a) primary structure (b) secondary structure (c) tertiary structure (d) quaternary structure
7. Assertion : The backbone of DNA and RNA molecules in a chain consisting of heterocyclic base,pentose sugar and
phosphate group.
Reason : Nucleotides and Nucleosides mainly differ from each other in presence of phosphate group.
8. Which of the following statements is not true about glucose .
(a) it is an aldose (b) on heating with HI it forms n – hexane .
(C) it is present in pyranose form (d) it gives 2,4 – DNP test.
9. Assertion : vitamin C cannot be stored in our body .
Reason : vitamin C is fat soluble and is excreated from our body in urine.
10. Give the reaction of glucose with acetic anhydride . presence of which group is confirmed by thr reaction ?
 2020
1. Read the given passage and answer the questions number 1 to 5 that follow :
Organic compounds containing amine as functional group are present in a vived variety of compounds, namely
amino acid , hormones, neurotransmitters, DNA, alkolids,dyes ets. Drugs including nicotine,morphine,codeine and
heroin,etc,which have physiological effects on humans also contain amino group in one form or another.Amines are
basic because of the presence of lone pair of electronson the nitrogen .Addition of nitrogen into an origin framework
leads to formation of two families of molecules ,namely amines and amides. As chemistry students,we must
appreciate the versatility of nitrogen.
1. What are amino acids ?
2. Why are amino acids Amphoteric ?
3. Give one point of difference between acidic and basic amino acid.
4. What are essential amino acids ?
5. Name the linkage formed when carboxyl end of one amino acid condenses with amino end of another amino
acid ?
2. Assertion : Albumin is a globular protein .
Reason : Polypeptide chain coils around to give a straight chain.
2018
1 Define the following with an example of each ;
(a) Polysaccharides (b) Denatured protein (c) Essential amino acid
2 (a) Write the product when D-glucose reacts with conc. HNO3.
(b) Amino acid shows amphoteric behavior. Why?
(c) Write one difference B/W α-helix and β- pleated structures of proteins.
2017
1) Name the common types of secondary proteins and give one point of difference.
2) Give one structural difference between amylose and amylopectin.
3) Which polysaccharide component of carbohydrate is commonly present in bread.
4) Give two examples of water soluble vitamins.
2015
1) Write the product obtained when D- glucose reacts with H2N-OH.
2) Amino acid shows amphoteric behavior. Why?
3) Why cannot vitamin C be stored in our body?
4) Which of the following is a disaccharides; starch, maltose, fructose, glucose.
5) What is the difference between fibrous and globular protein.
6) Write the name of the vitamin that causes bone deformities in children.
7) Difference between acidic amino acid and basic amino acid.
8) Write the name of the linkage joining two nucleotides.
9) Which of the following is a polysaccharide; starch, maltose, fructose, glucose.
10) Write one difference between α-helix and β-pleated sheet structure of protein.
11) Deficiency disease caused by; vitamin- B12, B-1, E,K,C
12) Which of the following is a oligosaccharide; starch, maltose, fructose, glucose.
13) What type of bonding stabilizes the α-helix structure of proteins.
14) Difference between native and denatured protein.
15) Amino –acid shows amphoteric behavior.
16) Which of the following is insoluble in water; insulin, hemoglobin, keratin
17 Write chemical reaction to show that glucose contain aldehyde group,
18) Give one structural difference between between amylase and amylopectin.
19) Name a protein and it shape present in oxygen carrier in human body.
20) Name two fat storing tissue of human body.
21) Give one reaction of D-glucose which cannot be explained by its open chain.
22) Difference between keratin and insulin.
23) Enumerate the reaction of D-glucose which cannot be explained by its open chain structure.
24) Amino acids may be acidic, basic or neutral. How this does happens?
25) What are essential & non-essential amino-acid? Name one of each type

2014
1. Which of the two components of starch is water soluble?
2 (1) deficiency of which vitamin causes night- blindness.
(2) Name the base that is found in nucleotide of RNA –only.
(3) Chemical property of glucose.
1 Deficiency disease of vitamins.
2 Give one example each of fibrous & globular protein.
3 Name the products of hydrolysis of sucrose. Why is sucrose not a reducing sugar?
4 Name the products of hydrolysis of maltose and lactose.
5 which colligative property is used to find the molecular mass of protein.

2013
1. What are the different types of RNA molecules which performs different functions?
2 What types of bonding helps in stabilizing the α-helix structure of protein?
3 What is Glycosidic –linkage.
4 What are the products of hydrolysis of sucrose , lactose ,maltose?
4 What happens when glucose is oxidized with nitric acid?
2011
1. Write the main structural difference between DNA & RNA. Of the four base name those which are common and
Different in both DNA & RNA.
2 Explain what is meant by (a) peptide linkage (b) pyranose structure of glucose. (c) Glycosidic linkage (d)
denaturation (e) nucleotide (f) anomers (g) essential amino acid. h) Nucleotide, nucleoside i) invert sugar
3 Describe the primary and secondary structure of proteins.
4 What is the essential difference between α and β-form of glucose?
2010
1 what happens when glucose is reacted with HI & Br2-water, HCN
2 What are vitamins and deficiency of which causes- pernicious anemia & convulsion.
3 Differentiate between globular and fibrous proteins.
4 What are monosaccharide’s?
5 What do you meant by Reducing & non-reducing sugar & invert sugar.
6 What is essential & non-essential amino acid? Give one example each.
7 Why is sucrose a non-reducing sugar?
8 What are the structural difference between a nucleoside & a nucleotide?
9 The two strands in DNA are not identical but complementary. Explain.
10 Mention the types of linkage responsible for formation of followings;
Primary structure of proteins, cross-linking of polypeptide linkage, α-helix formation, β-sheet structure.
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