Answer
To focus on near objects;
a. The suspensory ligament must be relaxed
b. The lens becomes thicker and rounder ( natural elasticity)
c. The ciliary muscles must contract
d. The image must focus on the photo receptors of the retina. where integration occurs. The fibers of the optic nerve (CNII) conduct visual neural stimuli to the brain
Work Step by Step
The light from an image < 2.5 ins away from the eye, diverges as it approaches the eye, and comes to focus
at a point behind the retina.
Three process must operate to focus the light on the retina;
a. Accommodation by the lens--lens becomes rounder and thicker under its own elasticity as suspensory
ligament relaxes
b. Constriction of the pupil; pupil made smaller by contraction of muscles of iris.
c. Convergence of the eyeballs: eyeballs rotate medially toward object being viewed.
