Assertion (A): Cyanide causes toxicity in man. Reason (R): Cyanid… - Vidyadip

MCQ

Assertion (A): Cyanide causes toxicity in man.
Reason (R): Cyanide impairs the functioning of our nervous system.

A
Both A and R are true and R is the correct explanation of A.
B
Both A and R are true but R is not the correct explanation of A
C
A is true but R is false.
D
A is false but R is true.

✓

Answer

(c) A is true but R is false.
Explanation: Cyanide inhibits the activity of cytochrome oxidase by combining it with its metallic ions. It has no structural similarity with the substrate of the enzyme, namely cytochrome C. Cytochrome oxidase is a respiratory enzyme. In its inhibition, the animal is unable to perform respiration properly and gets killed.

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