Optics of the Eye Flashcards
What gene triggers eye development in fruit flies?
Eyeless
What is the equivalent gene of eyelessness in mice and humans?
Smalleye (mice) and Aniridia (humans)
What do the genes eyeless, smalleye, and aniridia have in common?
They all belong to the Pax6 group of genes.
What is the function of the cornea and the lens in the eye?
They focus light on the retina.
Why do animals with different eyes share similar genes?
The Last Common Ancestor had photoreceptors, and Pax6 genes controlled the placement of light-sensitive patches.
What fluid fills the vitreous chamber of the eye?
Vitreous body
What fluid fills the anterior chamber of the eye?
Aqueous humor
What happens to the pupil in bright light and why?
It constricts to 1.5 mm, reducing the amount of light entering the eye.
What happens to the pupil in the dark and why?
It dilates to 8 mm to allow more light into the eye.
How does the eye focus light through the pupil?
a smaller pupil ensures each point on the retina receives light from one direction.
What role does the pupil play in controlling depth of field?
A constricted pupil gives a full depth of field, while a dilated pupil gives a shallow depth of field.
What is refraction?
The bending of light as it enters a medium with a different refractive index.
What is the function of the lens in refraction?
The lens adjusts its shape to focus light on the retina.
Which part of the eye is responsible for most of the eye’s refraction?
The cornea (2/3 of the refraction).
What is accommodation in the eye?
The process of making the lens rounder to focus on objects near them.
