Question

Why common substrate in cellular respiration is glucose not lipid?

Answer 1

Glucose is a ubiquitous fuel in biology. It is used as an energy source in most organisms, from bacteria to humans, through either aerobic respiration, anaerobic respiration, or fermentation. ... Glucose supplies almost all the energy for the brain, so its availability influences psychological processes.
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Answer 2

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Glucose is the basic substrate for cellular respiration, that releases energy in the form of ATPs to be used for all metabolic activities. ... Lipids are much richer source of energy. But still these are not used as the main source of energy as these are not converted into glucose directly, the basic respiratory substrate.

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