Plants ability to overcome cyanide poisoning

The presence of low levels of cyanide arrests cellular respiration in animals, yet has little or no effect on plants. Explain how plants are able to overcome the effect of cyanide poisoning.

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...idase makes up Complex IV of the electron transport chain, ATP cannot be formed and energy production is arrested. Some plants such as cassava, sorghum, and millet produce cyanide in the form of cyanogenic glycosides to prevent grazing damage from herbivores. To prevent inhibition of their own respiratory pathways, nearly all plants display at least some resistance to cyanide poisoning. Respiration rates typically remain at 10 - 25% of maximal activity when 1 mM cyanide is present. However, some plants, such as those listed above, retain full activity. The reason for continued respiration in plants despite the presence of cyanide is the presence of an alternative pathway at the level of ubiquinone represented by a single protein known as alternative oxidase (AOX).

The ...