The sense organs contain receptors that are sensitive to stimuli.
The
nervous system consists of the central nervous system - brain and
spinal cord -and peripheral nerves. Nerve impulses travel through the
axons of neurones - nerve cells. Reflex actions are fast, automatic and
protective responses.
Human vision is binocular, which gives us a
good perception of depth. Vision defects include short-sightedness,
long-sightedness and colour blindness.
