Why do plant tissue require less amount of energy in comparison to animal tissues

Why do plants have more dead tissues as compared to animals?

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Why do plant tissue require less amount of energy in comparison to animal tissues? 

Answer: Most of the plant tissues are dead, since dead cells can provide mechanical strength as easily as live ones, and need less maintenance.

Also plants have sedentary life i.e. they are stationary. Therefore plant tissues require less amount of energy.