biologie

• Biologie
• Secundair onderwijs

Image formation in the eye

the retina

• the light sensitive layer of the eye
• two layers:

      -pigmented layer

      -neural layer

the retina

• rods

-non color vision 

-low light vision

• cones

-color vision
-bright licht vision

-very detailed

photoreceptors

=the light sensing nerve cell located in the retina

(rods and cones)

the function

• captures the light
• helps transate it into the images you see
• the cells change the light energy into an elecrical signal
• the signal->your optic nerve->into your brain->becomes a picture of the world that we see

what detects the rods cells

1. bright light
2. low-light and non-color vision
3. bright light and color vision
4. low-light

what are the 2 layers of the retina

1. photoreceptor layer and the neural layer
2. pigmented layer and the green layer
3. pigmented layer and the neural layer
4. cones layer and the blue layer

short-sighted vision

• medical term : myopia
• closer objects are clear
• the eyeball grown to long (from front to back) 
• gets worse during adolescene (puberteit)-> gets better during early adulthood

long-sighted vision

• medical term: hyperopia
• closer object are blurry
• it happens when the eyeball is too short
• most children are born with it->it improves

for both of them

• refractive erros (vision problems that makes it hard to see clearly)
• easily corrected with glasses or contact lenses
• common signs

-tired eyes

-squiting eyes to see clearly

-eye strain and headaches 

How many procent of Americans are
nearsighted

1. 60%
2. 30%
3. 40%
4. 70%

What is a different word for hyperopia

1. myopia
2. long-sigted vision
3. near-sighted vision
4. rods

ciliary muscle

=muscle that controls the movement lens/pupil

• iris=colored part of the eye

• bij aanspanning van de ciliary muscle ontspant de lens en is het mogenlijk om dichtbij te zien
• bij ontspanning van de ciliary muscle spant de les aan en is het mogelijk om ver te zien

what are common signs of long-sighted and near-sighted vision