The Brain
 
Screen 1 of 2
Your
brain
is
made up
 
of
about
75
percent
water.
 
Our
brains
need
a lot
 
of
power
 
to
work
properly.
 
Sperm whales
have
 
the
largest
brains
 
of
any
animal,
 
 
over
five times
 
the
size
 
of
 
a
human
brain.