Question

Which of the following nutrients are energy sources for the brain?

• A. Glucose alone
• B. Triacylglycerol
• C. Glucose, fatty acids and ketone bodies
• D. Other metabolites

Answer 1

The correct option is A Glucose alone

Brain, unlike other tissues is almost exclusively dependent on glucose as the energy source. Fatty acids do not serve as fuel for the brain, because they are bound to albumin in plasma and so do not traverse the blood-brain barrier. In prolonged starvation, ketone bodies generated by the liver partly replace glucose as fuel for the brain, but brain cannot survive for very long without glucose.