Class 12 Chemistry - Chapter Biomolecules NCERT Solutions | What are the common types of secondary s
What are the common types of secondary structure of proteins?
There are two common types of secondary structure of proteins:
(i) ∝-helix structure
(ii) β-pleated sheet structure
∝- Helix structure:
In this structure, the -NH group of an amino acid residue forms H-bond with the 
group of the adjacent turn of the right-handed screw (∝-helix).
β-pleated sheet structure:
This structure is called so because it looks like the pleated folds of drapery. In this structure, all the peptide chains are stretched out to nearly the maximum extension and then laid side by side. These peptide chains are held together by intermolecular hydrogen bonds.
More Questions From Class 12 Chemistry - Chapter Biomolecules
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What happens when D-glucose is treated with the following reagents? (i)HI (ii)Bromine water (iii)HNO3
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How do you explain the absence of aldehyde group in the pentaacetate of D-glucose?
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Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
- Q:-
The melting points and solubility in water of amino acids are generally higher than that of the corresponding halo acids. Explain.
- Q:-
Define the following as related to proteins
(i) Peptide linkage (ii) Primary structure (iii) Denaturation.
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- Q:-
The two strands in DNA are not identical but are complementary. Explain.
- Q:-
Enumerate the reactions of D-glucose which cannot be explained by its open chain structure.
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Where does the water present in the egg go after boiling the egg?
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T/°C
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