33.Which of the following class of plant secondary metabolite is present specially in the order Brassicales?
(1) Glucosinolates      (2) Alkaloids
(3) Phenolics             (4) Terpenoids

Correct answer: (1) Glucosinolates

Explanation:

• Glucosinolates are sulfur-containing secondary metabolites found almost exclusively in plants of the order Brassicales, including the Brassicaceae family (mustard, cabbage, broccoli, etc.). They contribute to characteristic flavors and defense mechanisms in these plants.

• Alkaloids are a diverse class of nitrogen-containing secondary metabolites found widely across many plant families but not specific or limited to Brassicales.

• Phenolics are widespread in the plant kingdom and not specific to Brassicales.

• Terpenoids are the largest class of secondary metabolites but are universal, present in all plant orders.

Option-wise:

• (1) Glucosinolates — correct

• (2) Alkaloids — incorrect

• (3) Phenolics — incorrect

• (4) Terpenoids — incorrect

Glucosinolates are specialized sulfur-containing compounds uniquely abundant in the Brassicales order, offering chemical defense and the distinct pungency of mustard and related vegetables, while alkaloids, phenolics, and terpenoids are more broadly distributed plant metabolites.