The eye Flashcards
What is the role of the Cornea?
Refracts light towards the lens
What is the role of the Lens?
Fine-tunes the focusing of light on the retina
What is the role of the Iris?
Controls how much light enters the eye
What is the role of the Pupil?
The hole through which light enters the eye
What is the role of the Ciliary muscles?
Changes the shape of the lens for focusing
What is the role of the Suspensory ligament?
Holds the lens in place
What is the role of the Sclera?
A tough protecting coating
What is the role of the Retina?
Contains the light-sensitive receptor cells
What is the role of the Optic nerve
Sends electrical impulses to the brain
What is the role of the Blindspot
Where the optic nerve joins to the retina
What happens to the eye’s lens shape, ciliary muscles, and suspensory ligaments when an object is near?
Lens shape: Short and fat
Ciliary muscles: Contracts upwards
Suspensory ligaments: slackens/loosens
What happens to the eye’s lens shape, ciliary muscles, and suspensory ligaments when an object is far away?
Lens shape: Stretched and thin
Ciliary muscles: Relaxing
Suspensory ligaments: Taut/tight
What is Myopia?
Short-sightedness (can’t see in the distance)
What is wrong with a myopia eye and how can it be fixed?
The eye reflects too much light to be able to form an image in front of the retina and a concaved lens can fix it to reduce refraction
What is Hyperopia?
Long-sightedness (can’t see close-up)
What is wrong with a Hyperopia eye and how can it be fixed?
The eye can’t reflect enough light to be able to form an image behind the retina and a convex lens can fix it to increase refraction
