50 free The Brain trivia questions with answers — science & nature quiz, new questions added Aug 2026.
The brain weighs about as much as a bag of sugar, has the consistency of soft tofu, and burns a fifth of everything you eat. Aristotle thought it was a radiator for the blood. Descartes put the soul in its pine-cone-shaped gland. A Vermont railroad foreman took an iron bar through it and lived twelve more years. These 50 questions cover what a classroom or a pub round needs: the three main parts, the four lobes and what each does, the cortex and its folds, the corpus callosum, what 'cerebellum' means, the brainstem's job, the seahorse-shaped memory centre, the almond of fear, the hypothalamus and pineal gland, the three meninges and their Latin names, cerebrospinal fluid, the blood-brain barrier and the dye that revealed it, myelin and the nodes of Ranvier, neurons and synapses, Broca's area, Phineas Gage, H.M., Hans Berger's first EEG, Golgi and Cajal, phrenology, the ten percent myth and the brain that turned to glass at Vesuvius. Easy questions ask which lobe sees; hard ones ask who first called the brain the seat of the mind. Every answer is cited to a page we checked, with a short explanation so you learn something even when you miss. Play it solo or print it for a biology class.
30 of 50 questions with answers and explanations. Play the quiz
Q 01What are the three main parts of the human brain?
Cerebrum, brainstem, cerebellum
Together with the spinal cord it forms the central nervous system.
Q 02Roughly how much does an adult human brain weigh?
About 1.2 to 1.4 kg
That is about 2 percent of body weight, yet it uses up to 20 percent of the body's energy.
Q 03About how many neurons are in the human brain?
86 billion
There are roughly as many supportive glial cells as neurons.
Q 04The brain uses up to what share of the body's energy?
20%
It also takes about 20 percent of the oxygen and a quarter of the glucose.
Q 05What is the main fuel the brain normally runs on?
Glucose
During fasting it can switch to ketone bodies; low blood sugar can cause loss of consciousness.
Q 06How many lobes is each cerebral hemisphere conventionally divided into?
Four
Frontal, parietal, temporal and occipital, named after the skull bones above them.
Q 07Which lobe is dedicated to vision?
Occipital
Its name comes from Latin for 'behind the head'; damage to both sides can cause cortical blindness.
Q 08Which lobe handles executive functions such as planning, self-control and reasoning?
Frontal
It is the largest lobe and sits furthest forward.
Q 09What is the outer grey-matter layer of the cerebrum called?
Cerebral cortex
It is only 2 to 4 mm thick but deeply folded into ridges and grooves.
Q 10What are the ridges and grooves on the brain's surface called?
Gyri and sulci
The central sulcus separates the frontal and parietal lobes.
Q 11What does the corpus callosum do?
Connects the two hemispheres
It is about 10 cm long and carries 200 to 300 million axons.
Q 12What does the Latin name 'cerebellum' mean?
Little brain
Its tightly folded cortex conceals a surface like an accordion.
Q 13The cerebellum is best known for its role in what?
Motor coordination
It does not start movements but fine-tunes their precision and timing.
Q 14Which three structures make up the brainstem?
Q 21Which philosopher regarded the melatonin-producing gland as the seat of the soul?
René Descartes
He discussed it in Treatise of Man and The Passions of the Soul.
Q 22What are the three protective membranes around the brain and spinal cord called?
Meninges
Dura mater, arachnoid mater and pia mater, from outside in.
Q 23What does 'dura mater', the toughest outer brain membrane, mean in Latin?
Tough mother
The delicate inner pia mater is 'tender mother'.
Q 24The middle meningeal layer is named for its resemblance to what?
Midbrain, pons, medulla
It is only about 2.6 percent of brain weight but regulates heart rate and breathing.
Q 15The vasomotor and respiratory centres that keep you breathing sit mainly in which structure?
Medulla
Signals travel down the phrenic nerve to the diaphragm.
Q 16The hippocampus takes its name from its resemblance to which animal?
Seahorse
Venetian anatomist Aranzi likened it first to a silkworm, then a seahorse, in 1587.
Q 17The hippocampus is most important for which function?
Consolidating long-term memory
It is also key to the spatial memory used in navigation.
Q 18The amygdala is most associated with processing which of these?
Fear and emotion
Karl Friedrich Burdach named the almond-shaped structure in 1822.
Q 19Which almond-sized structure links the nervous system to the endocrine system via the pituitary?
Hypothalamus
It also governs temperature, hunger, thirst, sleep and circadian rhythms.
Q 20Which brain structure produces melatonin and is shaped like a pine cone?
Pineal gland
Descartes called it 'the principal seat of the soul'.
A spider web
The arachnoid mater is thin and transparent and cushions the central nervous system.
Q 25Roughly how much cerebrospinal fluid does a human produce each day?
About 500 mL
Only about 125 mL is present at any one time; it acts as a shock absorber.
Q 26Where is most cerebrospinal fluid produced?
Choroid plexuses of the ventricles
It is absorbed back into the blood through arachnoid granulations.
Q 27What is the living brain's consistency often compared to?
Soft tofu
It is very soft and gel-like, which is why it is suspended in fluid inside the skull.
Q 28What is the selective border of capillary cells that shields neural tissue from the bloodstream?
Blood–brain barrier
It is formed by tightly joined capillary cells, astrocyte end-feet and pericytes.
Q 29Whose dye experiments in the late 1800s stained every organ except the brain?
Paul Ehrlich
His dyes stained every organ except the brain; his student Edwin Goldmann later reversed the experiment.
Q 30What is the fatty material that insulates axons and speeds up nerve impulses?
Myelin
Gaps in it called nodes of Ranvier let the signal jump from node to node.