| A | B |
|---|
| 0.03 | Each blink is for _ seconds |
| 6 | # of muscles control each eye's movement |
| 30 | Blinking allows the eye to close approx _ minutes each day |
| 1/6 | What percent of the eye is open to external environment? |
| 2 to 10 | We blink every _ to _ seconds |
| Accommodation | Process whereby the lens changes shape to see objects at various distances |
| Aqueous Humour | Fluid in the eye that bathes the anterior region |
| Refracted | As light passes through the lens, it is _ |
| Change | To focus light, the lens must _ its shape. |
| Conjunctiva | Membrane that lines the eyelid and covers the anterior of the eye |
| Convergence | Simultaneous inward movement of both eyes (towards each other) in order to produce a single binocular vision of an object |
| Crystalline Lens | Adjusts the thickness and shape of the lens (refraction) |
| Elasticity | With aging the lenses lose some _ |
| Fovea | Area of sharpest vision |
| Lacrimal Ducts | Tear ducts |
| Lens Accommodation | Changing of lens shape |
| Blind spot | Region where optic nerve meets the retina and is insensitive to light |
| Optic Nerve | Nerve carrying impulses - traveling to and from the brain |
| Reading Glasses | Provide additional refraction the lenses can no longer provide. |
| Refraction | Bending of light rays (focusing) |
| Sense Organ | Receptors with sensitive cells activiated by a form of energy or stimuli in the internal or external environment |
| Vitreous Chamber | Cavity behind the lens containing vitreous fluid |
| Vitreous Humour | Maintains shape of eyeball |
| Choroid | Supplied eye with nutrients and oxygen |
| Sclera | Protects the eyball |
| Orbit | Space in which the eyeball sits |
| Presbyopia | Old sight |
| Astigmatism | Caused by an uneven curvature of the cornea |
| Convex | Converging lens |
| Concave | Diverging lens |
