Which structure changes lens shape to focus on near objects?

Which structure changes lens shape to focus on near objects?

• A. Iris
• B. Ciliary Body
• C. Retina
• D. Cornea

Answer: (B)

Accommodation is how the eye adjust its focusing for objects up close. When you shift focus to something near, the ciliary muscle in the ciliary body contracts. This tightens the surrounding area and releases tension on the zonular fibers that pull on the lens. With less tension, the lens becomes more curved and thicker, increasing its refractive power so light focuses properly on the retina. When looking at distant objects, the ciliary muscle relaxes, the zonules pull harder, and the lens flattens, decreasing its optical power. The iris, retina, and cornea don’t change the lens shape for accommodation—the iris controls pupil size, the retina detects the image, and the cornea provides most of the eye’s refractive power but remains relatively fixed during focusing.

Accommodation is how the eye adjust its focusing for objects up close. When you shift focus to something near, the ciliary muscle in the ciliary body contracts. This tightens the surrounding area and releases tension on the zonular fibers that pull on the lens. With less tension, the lens becomes more curved and thicker, increasing its refractive power so light focuses properly on the retina.

When looking at distant objects, the ciliary muscle relaxes, the zonules pull harder, and the lens flattens, decreasing its optical power. The iris, retina, and cornea don’t change the lens shape for accommodation—the iris controls pupil size, the retina detects the image, and the cornea provides most of the eye’s refractive power but remains relatively fixed during focusing.