[Campbell Biology P.1171] Which of the following accurately describes the changes in the mamm... | Practice Question

Which of the following accurately describes the changes in the mammalian eye for near vision accommodation ?

  • A: Ciliary muscles contract, suspensory ligaments relax, lens becomes thicker and rounder.
  • B: Ciliary muscles relax, suspensory ligaments pull against lens, lens becomes flatter.
  • C: Ciliary muscles contract, suspensory ligaments pull against lens, lens becomes flatter.
  • D: Ciliary muscles relax, suspensory ligaments relax, lens becomes thicker and rounder.

Explanation

For near vision accommodation , the ciliary muscles contract, which pulls the choroid border toward the lens, thereby relaxing the suspensory ligaments. This relaxation allows the elastic lens to become thicker and more spherical, increasing its refractive power to focus light from nearby objects onto the retina.