Vision Steps Flashcards
Owls have tube shaped eyes to enable _
As much light as possible to reach retina
As much light to reach retina as possible gives them
Sharp night vision
- Córnea
On reaching the eye, light brought into focus by _
Cornea
Córnea also protects eyes _
Inner elements
Fluid called _ fills front part of eye (between cornea and iris)
Aqueous humor
Aqueous humor maintains pressure and carries _
Nutrients
Muscular iris controls
Size of pupil
_ forms ring around lens
Ciliary muscles
Ring of bone known as _ holds eye in place
Sclerotic ring
- Lens
The flexible lens _ the focus of the image
Fine-tunes
Ciliary muscles pull of lens, changing its shape to _
Create sharper focus
_ gives eye structure and shape
Vitreous humor
Vitreous humor is a _ behind lens
Gelatinous fluid
- Retina
_ forms on retina
Upside-down image
5.
On retina, _ turn light into electrical signals for the brain
Photoreceptors
Signals carried to brain along the _
Optic nerve
6.
Where optic nerve connects to retina, there are no _ creating a blind spot
Photoreceptor cells
