Why you never see cattle or goats browsing on weed Calotropis ?

Options

A. The plant produces highly poisonous tannins.
B. The plant produces quinine which is bitter in taste.
C. The plant produces poisonous cardiac glycosides.
D. The plantbears prickles.

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks why cattle or goats do not browse on the weed Calotropis. This implies that there is a specific reason related to the plant's characteristics or defenses.

2. **Identifying Calotropis**: Calotropis is a plant commonly found in abandoned fields. It is known for its resilience and ability to thrive in poor soil conditions.

3. **Plant Defense Mechanisms**: Plants, unlike animals, cannot move away from threats. Therefore, they have evolved various defense mechanisms to protect themselves from herbivores (animals that eat plants). These mechanisms can be morphological (physical traits) or chemical (toxic substances).

4. **Chemical Defenses in Calotropis**: Calotropis has developed a specific chemical defense mechanism. It synthesizes and stores toxic compounds known as cardiac glycosides. These compounds are harmful to herbivores.

5. **Effects of Cardiac Glycosides**: When herbivores like cattle or goats consume Calotropis, the cardiac glycosides can cause them to become sick. The symptoms can include discomfort and potentially lethal effects, depending on the amount consumed.

6. **Behavioral Adaptation of Herbivores**: After experiencing the negative effects of consuming Calotropis, herbivores learn to avoid this plant in the future. This avoidance behavior is a survival strategy that prevents them from consuming harmful plants.

7. **Conclusion**: The reason cattle or goats do not browse on Calotropis is due to its production of toxic cardiac glycosides, which make the animals sick, leading them to avoid the plant.

### Final Answer:
Cattle and goats do not browse on the weed Calotropis because it produces toxic cardiac glycosides that make them sick, leading to learned avoidance of the plant.

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