Senses 7-8

Question 1

aqueous humor

Answer 1

an anterior watery fluid in the eye. lies in between cornea and iris.

Question 2

vitreous humor

Answer 2

a posterior gelatinous fluid. fills most of the eye. behind the iris and pupil.

Question 3

cornea

Answer 3

The cornea is a clear tissue because of the fact that it does not have blood vessels. it is one of the most sensitive tissues of the body with the density of pain receptors 300-600 times greater than skin. The cornea contributes most of the eye’s focusing power but the focus is fixed.

Question 4

lens

Answer 4

is a layered tissue comprised of packed columnar cells and elastic fibers encased in a transparent capsule. and it has a biconvex shape

Question 5

accommodation

Answer 5

The lens has a biconvex shape and by changing the curvature of the lens, the focal distance of the eye can change so that the eye can focus on objects at various distances.

Question 6

presbyopia

Answer 6

the older you get the stiffer and less round the lens becomes and thus reducing the ability to accommodate

Question 7

ciliary body

Answer 7

a structure of suspensory ligaments that suspense the lens

Question 8

iris

Answer 8

Located between the cornea and the lens. is smooth muscle extension of the choroid, which regulates the amount of light entering the eye. colored part of the eye

Question 9

pupil

Answer 9

allows light to enter the eye

Question 10

smooth muscle layer of the iris

Answer 10

• dilator pupillae-which dilates the pupil when it contracts.
• sphincter pupillae-which constricts the pupil when it contracts.

Question 11

focal point

Answer 11

When light rays pass through the lens, bending occurs and the point at which they converge is called the focal point.

Question 12

retina

Answer 12

The retina is part of the neural component of the eye. the focal point lands on the retina causing a clear image if focused correctly.

Question 13

myopia

Answer 13

nearsightedness. occurs when the eye structure is too long. Thus, when light is focused from distant objects by the optical components the image appears blurry because the focal point doesn’t strike the eye in the right spot.

Question 14

hyperopia

Answer 14

Farsightedness. results from an eye that is too short, thus the focal point of near objects occurs behind the eye, as a result the image is not focused in the right place so that it appears blurry.

Question 15

astigmatism

Answer 15

is caused by an abnormally shaped cornea. Thus, at certain angles the image entering the eye is not bent correct and becomes blurry.