List of top Chemistry Questions on Biomolecules asked in CBSE CLASS XII

Answer the following case-based questions on biomolecules: \[ (a)\;\text{Write the name of basic building units of proteins and nucleic acids. How can you differentiate between fibrous and globular proteins on the basis of their structures?} \] \[ (b)(i)\;\text{What products would be formed when a nucleotide from DNA containing thymine is hydrolyzed?} \] OR \[ (b)(ii)\;\text{Write one structural difference between DNA and RNA.} \] \[ (c)\;\text{Give one example each of a fat-soluble vitamin and a water-soluble vitamin.} \]

Write the reactions of D-Glucose with the following:

(a) HI
(b) \(Br_2\) water
(c) Conc. \(HNO_3\)

Which of the following statements is not true about glucose?

Assertion (A): All naturally occurring \(\alpha\)-amino acids except glycine are optically active.
Reason (R): Most naturally occurring amino acids have L-configuration.

Write the reactions involved when D-glucose is treated with the following reagents:
(a) HCN
(b) Br\(_2\) water

Which vitamin is responsible for the coagulation of blood?

Which one of the following is a disaccharide?
\[ \text{Glucose, Lactose, Amylose, Fructose} \]

What is the difference between native protein and denatured protein?

Define the following terms:
(a) Denaturation of protein
(b) Invert sugar

Write the main product in each of the following reactions: 

What type of linkages hold monomers of proteins together?

Give one example each for Fibrous protein and Globular protein.

What is meant by zwitter ionic form of amino acids?

What are essential amino acids?

In aqueous media, which is a stronger reducing agent — Cr³⁺ or Fe³⁺ and why?

Write the reactions of glucose with
(a) HI
(b)\((CH_3CO_2)O\)