Human Eye And Colourful World Flashcards
(25 cards)
What is the function of the pupil in the eye?
The pupil controls the amount of light entering the eye
What happens to the eye’s lens during focusing?
The ciliary muscles modify the curvature of the eye lems
What is the minimum distance at which objects can be seen distinctly known as?
The near point of the eye (25cm)
What is cataract?
The condition in which the crystalline lens of people at old age becomes milky and cloudy
What do optic nerves do?
Send messages of the light sensitive cells to the brain
What material is eye or crystalline lens made up of? ?
fibrous and jelly-like substances.
What does light sensitivity refer to in the context of the eye?
The ability to detect light
What is the diameter of the eyeball?
2.3 cms
What is accommodation?
The ability of the eye lens to adjust it’s foxam length
What is a retina?
A light sensitive screen having enormous number of light sensitive cells
What is the cornea?
a transparent bulge on the front of the eyeball where the light enters the eye
OR
a thin membrane on the front of the eye where most of the refraction takes place
What is the crystalline (eye) lens?
it is a fibrous and jelly like material that provides finer adjustments of focal length required to focus on objects
What is the iris?
it is a dark muscular diaphragm that controls the size of the pupil and gives colour to the eye
What are ciliary muscles?
The muscles in the eyeball that modifies the curvature of eyelens
What are optic nerves?
The optic nerves are nerves attached to the retina that send the massages of the light sensitive cells to the brain
What is accommodation?
The ability of the eye lens to adjust it’s focal length
When we look at distant objects, ciliary muscles ____ and the lens becomes ___. This is focal length ___
Relax, thin and increases
When we look at nearer objects, ciliary muscles ____ and the lens becomes ___. This is focal length ___
Contract, thick and decreases
Define “near point of the eye”
(Short answer) -> the least distance of distinct vision
OR
(Long answer) -> the minimum distance at which the objects can be seen distinctively without strain
What is the near point of the eye?
25 cm
Define “far point of the eye”
The farthest point up to which the eye can see objects clearly
What does cataract cause?
Partial or complete loss of vision
How to restore the vision lost due to cataract?
Cataract surgery
What is myopia?
It is a condition where the distant objects cannot be seen clearly due to the far point of the eye being closer than infinity
