What transparent, biconvex structure changes shape to change the focal distance of the eye so that it can focus on objects at different distances?
Lens It is similar to the focusing of a photographic camera via the movement of its lenses.
What is the transparent front part of the eye which, while contributing most of the eye's focusing power, has a fixed focus?
What thin, circular structure in the eye controls the diameter and size of the pupil and the amount of light reaching through it?
What is an eye defect due to the abnormal formation of the cornea or lens resulting in an inability to see horizontal and vertical objects clearly, simultaneously?
