Visual System Flashcards
Which part of the electromagnetic spectrum can the human eye perceive?
a) Infrared
b) X-rays
c) Visible light
d) Ultraviolet
c) Visible light
What is the range of wavelengths for visible light?
a) 100–300 nm
b) 400–700 nm
c) 700–1200 nm
d) 10–100 nm
b) 400–700 nm
What happens when light enters a slower medium like water?
a) Reflection
b) Refraction towards the perpendicular plane
c) Refraction away from the perpendicular plane
d) Absorption only
b) Refraction towards the perpendicular plane
The iris controls:
a) The shape of the cornea
b) The amount of light entering the retina
c) The lens’ focal length
d) The pressure of the eye
b) The amount of light entering the retina
Which muscle is responsible for changing the lens’ shape for accommodation?
a) Iris muscle
b) Ciliary muscle
c) Rectus muscle
d) Oblique muscle
b) Ciliary muscle
The cornea contributes to:
a) Adjusting the color sensitivity of the eye
b) Focusing most of the light on the retina
c) Controlling the eye’s blood supply
d) Providing nutrients to the lens
b) Focusing most of the light on the retina
Hyperopia occurs when:
a) The eye is too long
b) The image forms before the retina
c) The lens loses flexibility
d) The image forms behind the retina
d) The image forms behind the retina
Myopia is corrected with:
a) Convergent lenses
b) Divergent lenses
c) Cylindrical lenses
d) Convex mirrors
b) Divergent lenses
Rods are concentrated in the:
a) Fovea
b) Periphery of the retina
c) Optic nerve head
d) Lens
b) Periphery of the retina
Which photoreceptor is sensitive to night vision?
a) Rods
b) Cones
c) Bipolar cells
d) Ganglion cells
a) Rods
The pigment in cones is:
a) Rhodopsin
b) Photopsin
c) Melanin
d) Hemoglobin
b) Photopsin
What is the recovery time for rods?
a) Immediate
b) 5 seconds
c) 30 minutes
d) 1 hour
c) 30 minutes
Presbyopia results from:
a) Overactive ciliary muscles
b) Decreased lens flexibility
c) Retinal detachment
d) Excessive accommodation
b) Decreased lens flexibility
Which technology helps patients with photoreceptor layer degeneration?
a) LASIK
b) Retinal implants
c) Corneal transplants
d) Convergent lenses
b) Retinal implants
Retinal implants primarily stimulate which cells?
a) Ganglion cells
b) Bipolar cells
c) Rods
d) Cones
b) Bipolar cells