Having 2 eyes rather than 1 allows us to judge distance more accurately.
Each eye forms a slightly different image due to the eyes being several centimetres apart. The area of overlap is where we can judge distances accurately.
Cornea = tough, transparent layer at the front of the eye, allows light to enter and begins to bring it into focus.
Iris = coloured part containing muscles, which alter the diameter(size) of the pupil.
Lens = flexible, transparent, biconvex structure which focuses light on the retina.
Retina = light sensitive layer containing rods (sensitive to dim light) and cones (sensitive to bright light and colour). Light is converted to nerve impulses in the rod and cone cells - photoreceptors.
Optic Nerve = carries electrical nerve impulses from the retina to the brain.
Our judgement of direction of sound is more accurate using two ears rather than one.
Auditory canal = air-filled tube, which directs sound waves onto the eardrum.
Ear drum = thin membrane that vibrates and passes sound onto middle ear bones.
Middle ear bones = amplify and transmit sound vibrations from…