Biomolecules

Previous Years' CBSE Board Questions

10.1 Carbohydrates

MCQ

1. Which of the following is a non-reducing sugar?
2. Sucrose (b) Maltose
3. Glucose (d) Lactose

2 The glycosidic linkage involved in linking the glucose units in amylose part of starch is

1. C₁ - C₆ α linkage(b) C₁ - C₆ β linkage
2. <math>C_1 - C_4 \alpha</math> linkage (d) <math>C_1 - C_4 \beta</math> linkage

(2023)

1. Which of the following sugar is known as dextrose?
2. Glucose (b) Fructose
3. Ribose (d) Sucrose (Term I, 2021-22)

1. <math>\alpha</math>-D(+) glucose and <math>\beta</math>-D(+) glucose are
2. geometrical isomers (b) enantiomers
3. anomers (d) optical isomers. (2020) Ap

1. Assertion (A): Sucrose is a non-reducing sugar. Reason (R): Sucrose has glycosidic linkage. (Foreign 2014)
2. Both Assertion (A) and Reason (R) are correct statements, and Reason (R) is the correct explanation of the Assertion (A).
3. Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A).
4. Assertion (A) is correct, but Reason (R) is incorrect statement.
5. Assertion (A) is incorrect, but Reason (R) is correct statement. (2020) [An]

VSA (1 mark)

1. Name the disaccharide which on hydrolysis gives two molecules of glucose. (One word, 2020)
2. Write the name of linkage joining two monosaccharides. (One word, 2020)
3. What is the basic structural difference between glucose and fructose? (Delhi 2019) R
4. Write the structural difference between starch and cellulose. (Al 2019, 2016)
5. Write the products obtained after hydrolysis of lactose. (Delhi 2019)

OR

Write the name of two monosaccharides obtained on hydrolysis of lactose sugar. (Delhi 2016)

Name a carbohydrate present in liver, muscles and brain. (2019C)

1. What are the hydrolysis products of sucrose ? (2019C)
2. Define the following with an example : Polysaccharides (1/3, 2018)

OR

Define the following term: Polysaccharides

(Foreign 2014)

Write the product when D-glucose reacts with conc.

HNO3. (1/3, 2018)

Which one of the following is a disaccharide: Starch,

Maltose, Fructose, Glucose? (Delhi 2015) Ev

1. Write the product obtained when D-glucose reacts with <math>H_2N - OH</math>. (Al 2015)
2. Which one of the following is a monosaccharide: starch, maltose, fructose, cellulose (Foreign 2015) [[[
3. Which of the two components of starch is water soluble? (Delhi 2014)

Write the product formed on reaction of D-glucose

with Br₂ water. (Delhi 2014)

Write the product formed when glucose is treated

with HI. (Delhi 2014) Ap

Define the following term: Anomers

(Al 2014, Foreign 2014)

Define the following term: Invert sugar

SAI (2 marks)

Give the reaction of heating glucose with

hydroxylamine. Presence of which group is

confirmed by this reaction? (2023)

Define the following terms:

1. (ii) Invert sugar (2020) R

Write the reactions showing the presence of

following in the open structure of glucose: (i) Enumerate the reactions of glucose which cannot be

explained by its open chain structures. (Delhi 2014C)

SA II (3 marks)

(a) What are the hydrolysis products of (i) Lactose,

1. Maltose? (b) Give the basic structural difference between starch and cellulose. (2023)

Write the reaction of glucose with

1. HCN (ii) Br₂ (iii) HI (2021 C)

Write chemical reactions to show that open

structure of D-glucose contains the following: (i) What happens when D-glucose is treated with the

following reagents?

1. Br₂ water (b) HCN
2. (CH₃CO)₂O (AI 2019)

1. Define the following terms:
2. Glycosidic linkage (ii) Invert sugar
3. Oligosaccharides (Al 2014)

10.2 Proteins

MCQ

β-pleated sheet structure in proteins refers to

1. primary structure (b) secondary structure
2. tertiary structure (d) quaternary structure.

(2023)

45. Amino acids show amphoteric behaviour. Why?

(AI 2015) (An

An α-helix is a structural feature of

1. sucrose (b) starch
2. polypeptides (d) nucleotides.

1. Complete the following analogy: Curdling of milk : A :: α-helix : B
2. A: Primary structure, B: Secondary structure
3. A: Denatured protein, B: Primary structure
4. A: Secondary structure, B: Denatured protein
5. A: Denatured protein, B: Secondary structure (Term I, 2021-22) An

1. Amino acids which cannot be synthesized in the body and must be obtained through diet are known as
2. acidic amino acids
3. essential amino acids
4. basic amino acids
5. non-essential amino acids. (Term I, 2021-22)

1. The helix structure of proteins is stabilised by:
2. peptide bond (b) hydrogen bond
3. disulphide bond (d) van der Waals' forces (2021C)

Peptide linkage is present in

1. carbohydrates (b) vitamins
2. protein (d) rubber. (2020) [1]

1. Amino acids are
2. acidic (b) basic
3. amphoteric (d) neutral. (2020) R

Assertion (A): Albumin is a globular protein. Reason (R): Polypeptide chain coils around to give a straight chain.

1. Both assertion (A) and reason (R) are correct

statements, and reason (R) is the correct (b) Amino acids show amphoteric behaviour. Why?

explanation of the assertion (A).

1. Both assertion (A) and reason (R) are correct statements, but reason (R) is not the correct explanation of the assertion (A).
2. Assertion (A) is correct, but reason (R) is incorrect statement.
3. Assertion (A) is incorrect, but reason (R) is

correct statement. (2020)

1. An α-helix is a structural feature of
2. sucrose (b) polypeptides
3. nucleotides (d) starch.

VSA (1 mark)

What is the difference between a glycosidic linkage and a peptide linkage? (2019) 🕕

Define the following terms with a suitable example

of each: (c)

1. Anomers (b) Essential amino acids

1. What is the difference between fibrous protein and globular protein? (1/3, Al 2017C, Delhi 2015)
2. Give one example each for fibrous protein and globular protein. (Al 2016, Delhi 2014)

What is the difference between acidic amino acids

and basic amino acids? (Foreign 2015)

1. What type of linkage is responsible for the formation of proteins? (Delhi, Foreign 2014)
2. Define the following term: Essential amino acids (AI 2014)
3. Define the following term: Denaturation of proteins (Foreign 2014)
4. Define the following term: Amino acids (Foreign 2014) R

SAL (2 marks)

Define denaturation of protein. What is the effect of

denaturation on the structure of protein? (2023)

1. (a) Write chemical reaction to show that open structure of D-glucose contains the straight chain.
2. What type of linkage is responsible for the formation of protein? (2023)

Define the following with an example of each:

1. (ii) Essential amino acids (2/3, 2018)

1. (b) Write one difference between \alpha-helix and β-pleated structures of proteins. (2/3, 2018)

SA II (3 marks)

1. (a) Write the product when D-glucose reacts with conc. HNO₃.
2. Write one difference between α-helix and β-pleated structure of protein. (2023)
3. Define proteins and classify them on the basis of their molecular shape. (2020C)

Differentiate between the following:

1. (ii) Peptide linkage and Glycosidic linkage (iii) Fibrous proteins and Globular proteins. (Delhi 2019) Ev

Define the following terms as related to proteins:

1. (iii) Denaturation (AI 2015, 2014)

What are essential and non-essential amino acids?

Give two examples of each. (AI 2014C)