Eye Flashcards
Fibrous tunic
- Outer portion of eye
- Sclera & cornea
Vascular tunic
- Middle portion of eye
- Choroid
- Ciliary body, lens, iris
Nervous tunic
- Inner portion of eye
- Retina, rods and cones
Sclera
- Tough, white, outer portion of eye
- Continuous w/ cornea
Cornea
- Transparent portion of anterior eye
- Avascular
- Bends and refracts light
Choroid
- Middle layer
- Contains blood vessels and darkly pigmented
- Ciliary body, iris, lens
Ciliary body
- Holds ciliary muscles (smooth)
- Attached to lens w/ suspensory ligaments to control lens shape
Iris
- Colored portion of the eye
- Smooth muscle ring w/ pupil in the middle
- Controls light entering pupil
Lens
- Transparent
- Boconvex
Retina
- Innermost layer of the eye
- Contains neurons sensitive to light;
Rods
- Photorecpetors
- Black and white
Cones
- Photoreceptors
- Color
Fovea centralis
- Area where light is focused
- Area of sharpest vision
Optic disc
-No photoreceptors; aka blind spot
Aqueous humor
- Clear, watery fluid
- Helps maintain intraocular pressure
Vitreous humor
- Jelly-like substance
- Behind lens & posterior portion of eye;
Glaucoma
-Too much intraocular pressure due to too much aqueous humor
Extrinsic eye muscles
-Skeletal muscles that move the eye
Intrinsic eye muscles
-Smooth muscles in the eye; involuntary
Eyebrows
- Accessory structure of eye
- Protects/keeps foreign particles out
Eye lashes
- Accessory structure
- Protects/keeps foreign particles out
Eye lids
- Accessory structure
- Helps with lubricating eye
Conjunctiva
-Mucus membrane lining the lid of eye
Conjunctivitis
- Inflammation of conjunctiva
- Caused by an infection or irritation
- Aka pink eye