Question

art - based question: special senses, question 11
1 part | -- of 1 point
2 tries left
during close vision, what actions must the eye take to bring an object into focus?

Explanation:

The question is about the eye's actions during close vision to focus an object. This relates to the anatomy and physiology of the eye, specifically the process of accommodation. In close vision, the ciliary muscles contract, which relaxes the zonular fibers. This allows the lens to become more convex (thicker) to increase its refractive power, enabling focus on near objects. Also, the pupils constrict (miosis) to reduce spherical aberration and the eyes converge (move medially) to align the visual axes for binocular vision.

Answer:

During close vision, the eye performs three main actions: 1) The ciliary muscles contract, causing the zonular fibers to relax. This allows the lens to become more convex (thicker) through its inherent elasticity, increasing its refractive power to focus on near objects (accommodation). 2) The pupils constrict (miosis) via the contraction of the sphincter pupillae muscles, which reduces spherical aberration and depth of field, helping to sharpen the image. 3) The eyes converge (move medially) as the medial rectus muscles contract, aligning the visual axes of both eyes to ensure the object is imaged on corresponding points of the retinas for binocular vision.