Question

Cattle or goats are never seen browsing on the weed, Calotropis. Select the correct option for the reason.

• A. The plant produces highly poisonous tannins.
• B. The plant produces quinine, which is bitter in taste.
• C. The plant produces the poisonous chemical, cardiac glycoside.
• D. The plant bears prickles.

Hint:

Calotropis makes cardiac glycosides, which are poisonous, so grazing animals avoid it.

Answer 1

The Correct Option is C

Step 1: Recall the topic:
Plants defend themselves against herbivores by thorns or by chemicals. This is part of the study of predation and defence.

Step 2: Calotropis example:
NCERT says that Calotropis produces highly poisonous cardiac glycosides. Because of this, cattle and goats avoid it.

Step 3: Check each option:
Tannins are made by many plants but they are not the defence named for Calotropis, so (A) is wrong.
Quinine is made by Cinchona, not Calotropis, so (B) is wrong.
Prickles are mechanical defences, as in Acacia and Cactus, so (D) is wrong.
Cardiac glycoside is correct, so (C) is the answer.

Final Answer:
Calotropis produces poisonous cardiac glycosides, option (C).