Internal Eye and Retina

In which layer of the eye are the photoreceptors found?

Retina

What are the other two tunics of the eye?

Fibrous Tunic and Vascular Tunic

What are the two parts of the retina?

Neural retina and pigmented retina

Which part of the retina stores Vitamin A?

Pigmented retina

What is the name of the brown, vascularized structure next to the retina that helps absorb light?

Choroid

How many types of photoreceptors are there?

2

How do rods and cones differ?

Rods: best for dim light; Cones: best for bright light and color vision

Where are rods and cones located on the retina?

Rods: most abundant in periphery; Cones: most concentrated in the fovea centralis

What do we call the area of the eye that has no photoreceptors?

Optic disc

In what order are the layers of the retina hit by a beam of light?

Ganglion cells > Bipolar cells > Photoreceptor cells

What is the order of activation of the layers of the retina by light?

Photoreceptor > Bipolar cells > Ganglion cells

The axons of which cells form the optic nerve?

Ganglion cells

Where does the optic nerve exit the eye?

Optic disc

What part of the brain helps process vision?

Occipital lobe

What is the path a ray of light takes to reach the retina?

Cornea > Aqueous humor > Pupil > Lens > Vitreous humor > Retina

What is refraction?

Bending of light as it passes through the eye

Where does refraction happen in the eye?

Cornea and Lens

What is the difference between myopia and hyperopia?

Myopia: nearsighted, light focuses in front of the eye; Hyperopia: farsighted, light focuses behind the eye

Which structures of the internal eye have parasympathetic innervation from cranial nerves?

Sphincter pupillae muscle (III) and Ciliary muscles (III)