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Various chemical compounds like nicotine, caffeine, quinine, strychnine, and opium, which are commercially derived from plants, serve as protective mechanisms for plants against herbivores and animals that feed on them. Which of the following statements is true?

1. Strychnine is an extremely poisonous, bitter, crystalline substance that is often used as a pesticide to eliminate small animals like rodents and birds.
2. Natality refers to the number of new individuals born in a population over a specific time, while mortality refers to the number of deaths. Population interaction describes how different populations influence each other within a community, and the sex ratio indicates the proportion of males to females in a population.
3. The relationship between female wasps and fig trees is an example of mutualism, where both species benefit. On the other hand, relationships such as orchids growing on trees, cattle egrets with grazing cattle, and clownfish with sea anemones are examples of commensalism, where one organism benefits without affecting the other.
4. Alstonia exhibits whorled phyllotaxy, where more than two leaves grow at a single node in a circular arrangement. In contrast, China rose and mustard display alternate phyllotaxy with one leaf per node, and Calotropis shows opposite phyllotaxy with paired leaves at each node.

Correct answer: Strychnine is an extremely poisonous, bitter, crystalline substance that is often used as a pesticide to eliminate small animals like rodents and birds.

Solution

The question discusses plant-derived chemical substances used as defenses against herbivores. Option A correctly describes strychnine, a plant-derived alkaloid used as a pesticide, aligning with the context of plant defense mechanisms.

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