By keeping the bulb in the center and orbiting the blue gel (for the iris) and the opaque disk (for the pupil) around the bulb, the eye can appear to gaze in different directions. By adjusting the ...

Adam Taylor, Professor and Director of the Clinical Anatomy Learning Centre at Lancaster University, explained the eye is ...

That coloured circle is called the iris and the black spot in the middle is the pupil. This is the part of the eye that lets the ... white and shades of grey, and the cones see the colours ...