For the defence against predators, butterflies become highly distasteful due to having certain chemical in their bodies. What is the source of the chemical?

Options

A. The butterflies has genes for synthesis of this chemical in its each and every cell.
B. The butterfly acquires this chemical during its caterpillar stage by feeding on a poisonous plant
C. This chemical accumulates in the cells of butterfly when it feeds sap of a plant
D. The butterfly synthesis secretes the chemical from its corpus allatum.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the source of the chemical that makes butterflies distasteful to predators as a defense mechanism.

2. **Identifying the Example**: The Monarch Butterfly is a well-known example of a butterfly that is distasteful to predators. This butterfly has developed a defense mechanism that makes it unpalatable.

3. **Caterpillar Stage**: During its caterpillar stage, the Monarch Butterfly feeds on certain plants that are poisonous. This is a crucial point because the caterpillar stage is when the butterfly acquires the chemical that contributes to its distastefulness.

4. **Source of the Chemical**: The chemical that makes the Monarch Butterfly distasteful comes from the poisonous plants it consumes during its caterpillar stage. By feeding on these plants, the caterpillar absorbs and stores the toxic compounds.

5. **Conclusion**: Therefore, the source of the chemical that makes butterflies like the Monarch distasteful to predators is the poisonous plants that the caterpillar feeds on.

**Final Answer**: The butterfly acquires this chemical during its caterpillar stage by feeding on poisonous plants.

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