When viewing objects at different distances, the lens of the eye automatically changes shape in a process known as
The correct answer and explanation is:
The correct answer is accommodation.
Accommodation is the process by which the eye’s lens changes shape to focus light from objects at different distances onto the retina. This automatic adjustment allows clear vision whether an object is near or far.
The lens of the eye is flexible and located behind the iris. When viewing distant objects, the ciliary muscles surrounding the lens relax. This relaxation causes the suspensory ligaments to pull tight, flattening the lens. A flatter lens bends light rays less, allowing them to focus properly on the retina when the object is far away.
When looking at nearby objects, the ciliary muscles contract. This contraction reduces tension on the suspensory ligaments, allowing the lens to become thicker and more curved. A thicker, more curved lens bends light rays more sharply so they focus correctly on the retina for close objects.
This dynamic change in lens shape is crucial because the eye must focus light precisely on the retina to produce a clear image. Without accommodation, objects at different distances would appear blurry.
Accommodation also declines with age in a condition called presbyopia. The lens loses its elasticity and cannot thicken sufficiently, making it difficult to focus on close objects. This is why many people require reading glasses as they get older.
In summary, accommodation enables the eye to maintain a sharp image on the retina regardless of whether an object is near or far by changing the lens’s curvature through the action of ciliary muscles. This process is automatic and essential for clear vision.