Lab Practical 1 Flashcards
What are the sensory receptors located in the head
Nose Tongue Eyes Ears
Parts of the vision system
Eyes Optic nerves Vision centers in the brain Accessory structures
Processes light to produce images Three layers Two chambers Specialized parts
Eye
White of the eye Protects the eye Sense receptors Cornea
Outer layer of eye (sclera)
Cornea
Front of eye “Window” which allows light into eye Bends light as it enters
Contains blood vessels Iris Ciliary body Lens
Middle layer of the eye (choroid)
Iris
Colored part of the eye Muscle that contracts and relaxes to open/close the pupil Regulates the amount of light that enters the eye
Ciliary body
Muscles Controls the shape of the lens
Lens
Posterior to the iris Focuses light on the retina
Visual receptors Optic disc
Inner layer of the eye (retina)
Types of visual receptors
Rods Cones
Rods
Sensitive to light Will function in dim light Provide “Limited” night vision Do not provide sharp image Do not detect color
Cones
Function in bright light Sensitive to color Provide sharp images
Optic disc
Where the optic nerve enters the retina
Chambers of the eye
Anterior Posterior
Anterior chamber of the eye
Front of lens Filled with aqueous humor
Nourishes and bathes the anterior eye Watery
Aqueous humor
Posterior chamber
Behind lens Contains vitreous humor
Maintains shape of eyeball Holds retina in place Jelly-like
Vitreous humor
Eye orbits
Eye sockets Form a protective shell around the eyes
Eyelids
Skin, muscle and connective tissue Blinking
Blinking
Prevents surface from drying out Keeps foreign material out of eye
Conjunctivas
Mucus membranes Line inner surfaces of eyelids
Lacrimal apparatus
Lacrimal glands Nasolacrimal ducts
Lacrimal glands
Lateral edge of eyeballs Produce tears
Nasolacrimal ducts
Medial aspect of eyeballs Drain tears into nose
How many extrinsic eye muscles are there?
6