Final answer:
The brain consumes about 20% of the body's total energy, despite only making up about 2% of the body's weight.
Step-by-step explanation:
The brain consumes about 20% of the body's total energy, despite only making up about 2% of the body's weight. It uses mostly glucose for energy and is even able to store some glucose in the form of glycogen. The brain is the most complex organ in the body, with billions of neurons and synapses that require a lot of energy to function.