Q21 of 805 Page 1

Explain with the help of two examples how certain plants have evolved morphological and chemical defences against primary consumers such as cows and goats.

Plants have evolved morphological and chemical defenses, which inhibits the primary consumers such as cows and goats as a defence mechanism. Examples are:

(i) The cactus has evolved morphologically to produce thorns as a defence against cows and goats. The thorns are sharp and cows and goats cannot eat them.


ii) Highly poisonous glycosidases are produced by Calotropis plant to inhibit cows and goats from eating it. Other chemical substances are nicotine, caffeine, opium.


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(a) Write how e-waste is generated.


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(c) How have the developed countries exploited the developing countries with respect to e-waste managements ?