1 / 16

THE EYE

THE EYE. CHAPTER 10. QOD #1: Pre-Test. 1.) What are the 5 senses? 2.) T/F Of all the sensory receptors in the body, 70% are in the eyes. 3.) T/F Your eyebrows have no function. 4.) T/F If you are colorblind, you do not see any color.

coby
Download Presentation

THE EYE

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. THE EYE CHAPTER 10

  2. QOD #1: Pre-Test 1.) What are the 5 senses? 2.) T/F Of all the sensory receptors in the body, 70% are in the eyes. 3.) T/F Your eyebrows have no function. 4.) T/F If you are colorblind, you do not see any color. 5.) T/F If you are farsighted, you cannot see objects that are in close proximity. 6.) _________ is caused by an increase in pressure in the eye.

  3. The eye • 70% of sensory receptors in the body are found here. • Housed in the orbit of skull and surrounded by fat, blood vessels, nerves, and connective tissues. • 2.5cm in diameter • 3 layers (tunics/coats) • Outer layer (fibrous) • Protective, refracts light • Includes cornea and sclera • Middle layer (vascular) • Contains pigments to keep eye dark inside • Includes choroid coat, ciliary body, lens, iris, pupil, aqueous humor. • Inner layer (nervous/sensory) • Visual receptors • Contains retina, fovea, optic disc, vitreous humor

  4. Pathway of Light Cornea Aqueous humor Pupil Lens Vitreous humor Retina

  5. EYE PHYSIOLOGY • Refraction: occurs when light waves are bent • Normal • Image is upside down • Visual cortex of brain interprets it in its proper position

  6. Physiology cont… • Accomodation: • Occurs when the lens adjusts its shape to focus on objects. • Ciliary muscles and suspensory ligaments aid in doing this • When the ligaments pull outward the lens flattens and focuses on distant objects • When ligaments are relaxed the lens is more convex (thickens) focusing on closer objects

  7. VISUAL ACUITY • Ophthalmoscope: instrument that illuminates the interior of eyeball allowing the inside to be seen. • Snellen eye chart: • measure acuity • 20/20 normal vision • Higher the number the poorer the vision

  8. Eye problems • Myopia: near sighted • Hyperopia: far sighted • Emmetropia: normal vision • Astigmatism: cornea/lens developed an irregular shape • Strabismus: cross-eyed • Diplopia: double vision (can be caused by one eye deviating from line of vision). • Blindness: most common cause is loss of transparency of the cornea • Cornea transplant (high success rate b/c no blood vessels)

  9. Eye problems cont.. • Cataract: lens becomes cloudy (laser surgery to fix) • Glaucoma: increase in intraocular pressure, caused by an increase in aqueous humor • Tonometer: instrument measuring pressure • Night blindness: poor vision in dim light resulting from a vitamin A deficiency.

  10. Normal Vision ColorBlind  Color Blindness: Genetic disorder carried on the X chromosome. Most common is red/green color blindness.

  11.  Normal Vision Color Blind 

More Related