Test: Primary & Secondary Metabolites - NEET MCQ

Primary metabolites are essential for basic cellular functions such as growth, development, and reproduction. Amino acids and sugars fall into this category because they are fundamental components of proteins and energy production, respectively. Secondary metabolites, such as flavonoids and alkaloids, do not have a direct role in these primary physiological processes but are often involved in plant defense mechanisms and other ecological interactions. Therefore, the correct classification is (i) Primary, (ii) Primary, (iii) Secondary, (iv) Secondary, making Option A the correct choice.

Assertion A is true as secondary metabolites such as rubber and essential oils generally do not have identifiable roles in the normal physiological functions of the organisms that produce them. Reason R correctly explains this by stating that these metabolites are involved in ecological functions such as defense, rather than in primary metabolic processes. Therefore, Option A is correct as R is the correct explanation of A.

Primary metabolites in the list (Amino acids, Glucose, Fructose, Fatty acids, Thymine, Uracil) are directly involved in essential physiological processes and number six. Secondary metabolites in the list (Alkaloids, Abrin, Ricin, Carotenoids, Lectins, Drugs) serve more specialized ecological or pharmacological roles and number six. Hence, the correct answer is six primary and six secondary metabolites, making Option c correct.