Eye Flashcards
What is the anterior chamber filled with?
Aqueous humor
What is the conjunctiva?
Mucous membrane that covers front of eye and lines eyelids
What are the functions of the conjunctiva?
Lubricates eye
Immune surveillance - prevents microbe entry
What is the function of the sclera?
Protect the eye
What is the function of the iris?
Control the diameter of the pupil - amount of light that reaches retina
What is the nerve supply to circular muscle of iris?
Short ciliary nerves
Which cranial nerve do the short ciliary nerves travel along?
Oculomotor
What is the nerve supply to the radial muscle of iris?
Long ciliary nerves
Which cranial nerve do the long ciliary nerves travel along?
Opthalmic
What nerve supplies the ciliary muscle in the ciliary body?
Short ciliary nerve
How does contraction of ciliary body affect vision?
Short range focus - lens more spherical
How is the aqueous humor reabsorbed?
Anterior chamber -> trabecular network -> Schlemm’s canal -> episcleral veins
Which eye disease is associated with problems of aqueous humor drainage?
Glaucoma
What is the function of the choroid layer of the eye?
Provides oxygen/nourishment to outer layers of retina, limits uncontrolled reflection in eye
What two layers is the retina made up of?
Outer pigment layer
Multi-layered neural retina
What are the three main differences between the function of rods and cones?
Rods: - Dim light - Perceive flicker well - Low acuity Cones: - Bright light - Less response to flicker - High acuity
What is the blind spot called?
Optic disc/papilla
Why is the blind spot blind?
No photoreceptors
What is the macula lutea?
Yellow pigmented zone
What is the fovea?
Centre of the macula lutea that’s specialised for visual acuity
How is the fovea specialised?
Only contains cones, no blood vessels to distort image
Which layers of the retina does the uveal circulation supply?
Outer and middle layers of retina
Which layer of the retina does the retinal circulation supply?
Inner layer of retina
