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Organisms and Populations — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations3 Marks
Question
Explain with the help of two examples, how certain plants have evolved morphological and chemical defenses against primary consumers such as cows and goats.
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Answer

  1. Thorns and spines are the most common morphological means of defence.

Example: spines of Acacia and cacti.

  1. Many plants produce and store chemicals, which when consumed by the herbivores make them sick, inhibit digestion, disrupt reproduction or even kill them.

Example: Calotropis produces highly poisonous cardiac glycosides.

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