Q 01/05

What are the three main parts of the human brain?

A) Cerebrum, brainstem, cerebellum

B) Cortex, thalamus, spinal cord

C) Frontal, parietal, temporal

D) Neurons, axons, dendrites

Answer · why

A) Cerebrum, brainstem, cerebellum

Cerebrum, brainstem, cerebellum. The cerebellum takes up only about a tenth of the brain's volume, yet it holds more neurons than the rest of the brai...

Q 02/05

Roughly how much does an adult human brain weigh?

A) About 0.4 kg

B) About 1.3 kg

C) About 4 kg

D) About 12 kg

Answer · why

B) About 1.3 kg

About 1.3 kg. Albert Einstein's brain weighed 1,230 grams, a little lighter than the average man's.

Q 03/05

About how many neurons are in the human brain?

A) 860 million

B) 8.6 billion

C) 86 billion

D) 860 billion

Answer · why

C) 86 billion

86 billion. Suzana Herculano-Houzel reached the figure by dissolving donated brains into a 'soup' and counting the nuclei; textbooks had long said 100...

Q 04/05

The brain uses about what share of the body's energy at rest?

A) 1%

B) 5%

C) 20%

D) 50%

Answer · why

C) 20%

20%. Hard thinking barely raises it: the brain burns nearly as much energy at rest as it does on a difficult problem.

Q 05/05

What is the main fuel the brain normally runs on?

A) Glucose

B) Protein

C) Fat

D) Cholesterol

Answer · why

A) Glucose

Glucose. The brain needs a constant supply of it from the blood, which is why a steep fall in blood sugar can cause loss of consciousness.