Glucose is virtually the sole fuel for the human brain, except during prolonged starvation. The brain lacks fuel stores, thus requires a continuous supply of glucose. It consumes about 120 g daily which corresponds to an energy input of 420 kcal (1760 KJ), accounting for some 60% of the utilization of glucose by the whole body in the resting state.
Answer:
Red blood cells are adapted to their function by:
1) They contain haemoglobin - a red protein that combines with oxygen. they have no nucleus so they can contain more haemoglobin.
2) They are small and flexible so that they can fit through narrow blood vessels.
3) They have a biconcave shape (flattened disc shape) to maximise their surface area for oxygen absorption.
Hope this helps! :D
