Anatomy and Functional Structure of the Eye

Question 1

eye Lid

Answer 1

• external protective sheild
• cleanses and moisturizes the eye
• blocks out debris and light

Question 2

Cornea

Answer 2

• internal sheild for eye
• very sensitive
• refracts light waves
• highest concenteration of nerve receptors

Question 3

Pupil

Answer 3

• adjustable tunnel through which light enters

Question 4

Iris

Answer 4

• sensetive to amplitude of light waves
• melanin protects retina
• donut shaped muscle that regulates pupils diameter

Question 5

Lens

Answer 5

• flexible transparent disc that focuses light waves onto retina
• cilliary muscles bulge for near, flatten for far

Question 6

Vitreous Humor

Answer 6

• clear gelationus flud that ocular chamber is filled with to preserve the eyes spherical shape

Question 7

Aqueous Humor

Answer 7

• clear gelatinous fluid between cornea and iris

Question 8

Retina

Answer 8

• transduces light waves into neural impulses

Question 9

Rods

Answer 9

• 120 million per eye
• concenterated in outer rings of the retina
• peripheral vison and night vison
• allows us to see shades of grey

Question 10

Cones

Answer 10

• 6 million per eye
• concenterated within the inner corners of the retina
• color detection
• acuity

Question 11

Macula

Answer 11

• center of retina
• contains most cones
• macular degeneration is the most common cause of blindness

Question 12

Fovea

Answer 12

• center of the macula
• focus point for the lense

Question 13

Optic Nerve

Answer 13

• nerve conecting retina to the reticular activiating sytem
• • transmits neural impules to the brain

Question 14

Blind Spot

Answer 14

• places in the retins where the optic nerve is attached
• absense of rods and cones

Question 15

Selera

Answer 15

• outer membrane of the eye where occular muscles and blood vessels are attached

Question 16

How do eyes adjust to limited light?

Answer 16

• the muscles contract caussing the opening to narrow when bright and dialte when dim
• dilation to maximize absorption of light
• photoreceptors sensitivity transfers from the cone receptorsd to the rod photoreceptors
• • cones - sensitive to hightamplitude of light waves
• rods - sensetive to low amplitude of light waves

Question 17

Visual Accomidation

Answer 17

• ability of the lenses to change the contour of its shape to allow it to focus far and near
• cilliary muscles relax, allowing lenses to stretch or flatten to be able to see into the distance