As a person ages, presbyopia develops, reducing near vision acuity. Which mechanism explains why the crystalline lens curvature hardens with age, leading to this reduced accommodation?

💡 Explanation

Presbyopia occurs because the lens loses elasticity due to increased crosslinking of its proteins. This decreased elasticity reduces the lens's ability to change curvature for focusing on near objects; therefore, protein crosslinking is the primary mechanism, rather than changes in pupillary dilation, retinal pigment epithelium, or vitreous humor.

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