Question

Assertion :All proteinaceous enzymes have a three dimensional structure. Reason: The secondary structure of protein is according to amino acids present inside the polypeptide.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

All proteinaceous enzymes have a three dimensional structure. It helps in easy binding of the cofactors which makes the enzyme more biologicaly active. The secondary structure of protein is according to amino acids present inside the polypeptide.

Alpha helix structure of protein is a form of secondary structure of the protein. It is formed due to formation of hydrogen bonds between backbone amide and carbonyl groups. The hydrogen bonds linkage are formed between N-H group of one amino residue with a C=O group of another amino acid, which is placed in 4 residues earlier. β-pleated secondary protein structure is formed by the parallel or anti parallel polypeptide chain linked together by H - bonds. It is stabilized by the hydrogen bonds formed between NH and Co of the adjacent polypeptide chain. The distance between the adjacent amino acids are 3.5 A${}^o$.

So, the correct answer is option B.