What is the transparent front part of the eye which, while contributing most of the eye's focusing power, has a fixed focus?
Cornea The curvature of the lens is adjusted to "tune" the focus depending upon the object's distance.
What transparent, biconvex structure changes shape to change the focal distance of the eye so that it can focus on objects at different distances?
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?
