Special Senses - The Eye Flashcards
What component of the eye is found within the inner most part?
the retina
What cells are adapted to respond to light stimulus?
photoreceptor cells
What sort of vision is seen in cats and dogs?
binocular (3d vision)
What sort of vision is seen in prey species?
monocular (2d vision)
The eye consists of 3 main parts, what are they?
- the eyeball
- the extrinsic muscles
- the eyelids
What 2 things protect the eye?
bony orbit, eyelids and conjunctiva
What three glands secrete/contibute towards tears?
- lacrimal
- meibomian
- harderian or nictitans
What duct commonly gets blocked in rabbits?
nasolacrimal
What helps reinforce the eye in avian species?
the sclerotic ring
The eye can be divided into 3 (chambers and body), what are they?
- anterior chamber
- posterior chamber
- vitreous body
Hint: 3 parts
The eyeball comprises of what?
the sclera, uvea and retina
What helps to improve night vision in animals?
Tapetum Lucidum
What component controls the pupil to dilate and contract?
The iris
What is the nerve supply to the iris?
Oculomotor nerve
What is the function of the pupil?
Allows light into the retina.
Define: Mydriasis & Miosis
Mydriasis - enlarged pupils
Miosis - small pupils
What is the term given to a patient with different sized pupils?
Aniscoria
What component of the eye focuses light onto the retina?
The Lens
How is information trasmitted from the retina to the brain?
The optic nerve
What are the two types of photoreceptors?
rods and cones
Explain the formation of an image in 6 steps:
- ight rays pass through cornea
- light rays pass through pupil
- light hits the lens and is reflected onto retina
- light hits photoreceptors, nerve impulses sent to brain
- info carried to brain is interpreted as an image
- image formed on the retina is inverted but brain processes it the right way up.
