Explanation The image that falls on the retina is no longer on the focus when the object lies on a distance less than twenty feet to the eye. There are three events that bring the object to focus: Accommodation: The ciliary muscles' contraction due to the stimulation by the oculomotor nerve (III) occurs. The lens become more spherical which causes more refraction leading to focusing of the image on the retina...

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Question

Chapter 15.3, Problem 19AYP

Summary Introduction

To analyze:

The processes that occur to focus an object on the retina that is closer than 20 feet

Introduction:

The focusing system of the eye comprises of the cornea and the lens. The distant vision is when the object of sight is placed at or farther than the 20 feet from the eye whereas, the near vision is when the object of sight is placed at or closer to a distance of twenty feet from the eye.

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Chapter 15.3, Problem 18AYP

Chapter 15.3, Problem 20AYP

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Using a line diagram, show how parallel rays of light are brought to a focus on the retina. Explain how this focus is maintained as the distance from the object to the eye is increasedor decreased (that is, explain accommodation).

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Chapter 15 Solutions

SEELEY'S ANATOMY+PHYSIOLOGY

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Solution Summary: The author explains that the focusing system of the eye comprises the cornea and lens. Accommodation, pupil constriction, and convergence are the three events that bring the object to focus.

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