Senses Continued Flashcards
What are the accessories stuctures of the eye?
Palpebrae (eyelids)
Medial and lateral canthus (corners of the eye)
Palpebrae fissure (opening between palpebrae)
Eyelashes (root hair plexus triggers blinking reflex)
Conjunctiva (epithelial of the eyelids)
What are the glands of the eye?
Gland of zeis, tarsal glands, lacrimal glands
What is conjunctivitis?
Pink eye
What is the function of the conjunctiva?
Covers the inner lining of eyelids and outside of eye
Fluid production helps prevent dryness
What are the Glands of Zeis?
They are Sebaceous glands
They are associated with eyelashes
Infections can cause sty
What are the tarsal glands?
They secrete a lipid rich product
They keep the eyelids from sticking together
They are located along the inner margin of eyelids
What are the lacrimal glands?
They produce tears
They are located at superior lateral portion of the eye
What structures make up the lacrimal apparatus?
Lacrimal glands (produce tears)
Lacrimal canaliculi
Lacrimal sac
Nasolacrimal duct (what causes a runny nose when crying)
What are the parts of the eyes?
Sclera
Cornea
Pupil
Iris
Lens
Retina
Anterior cavity
Posterior cavity
Three tunics (fibrous tunic, vascular tunic, neutral tunic)
What is the fibrous tunic?
It is made up of the sclera and cornea (modified sclera)
It provides protection
It is an attachment site for extra-ocular muscles
What is the vascular tunic?
It contains the iris, blood vessels, pigment, and smooth muscles
(The pigment creates eye color)
Iris contracts to change diameter of pupil
What is the neural tunic?
It’s also called the retina
It has 2 layers (pigmented outer layer and an inner neural layer)
Retina cells are photoreceptors
Rods for light and cones for color
Describe the pathway of light through the eye
Light waves travel through the cornea
Then anterior chamber
Then pupil
Then posterior chamber
Then it travels through the lens to focus the image on the retina which creates depolarization of neural cells
Which area has 100% cones
Fovea centeralis
(Works best in bright light)
(Best color vision when object is focused on fovea centralis)
What area has 0% rods or cones
The optic disk area (aka blind spot)
