Explain the role of the ciliary muscle in the change in the thickness of the eye lens when a student sitting in a classroom shifts his eyes from the letter written on the whiteboard to a distant object seen out of the window.

Question

Arpit Sundas · Accepted Answer

The ciliary muscle is a ring of smooth muscle in the eye that controls the shape of the lens to facilitate focusing on objects at varying distances.

When a student shifts their gaze from the whiteboard to a distant object, the ciliary muscle relaxes, causing the lens to become thinner for distant vision. This reduction in thickness allows light rays from faraway objects to be properly focused on the retina, ensuring clear vision.

Conversely, when focusing on nearby objects, the ciliary muscle contracts, thickening the lens for better clarity.