Lecture 21 Eyes

What is the highlighted part of the eye?

 Cillary body  

What is the highlighted part of the eye?

Cornea 

What is the highlighted part of the eye?

Iris 

What is the highlighted part of the eye?

Pupil 

What is the highlighted part of the eye?

Lens 

What is the highlighted part of the eye?

Sclera 

What is the highlighted part of the eye?

Retina 

What is the highlighted part of the eye?

Optic nerve 

What is the highlighted part of the eye?

Optic disc 

What is the accessory anatomical structure of the eye?

• Eyebrows

• Eyelids

• Conjuctiva

• Lacrimal Apparatus

• Extrinsic eye muscle

What is the function of the Cornea?

• Focus light onto the retina

• Protects against dirt, germs, and UV ray

What is the function of the sclere?

Provides structure and protection

What is the function of the optic nerve?

Carries visual information from the retina to the brain

What is the function of the lens?

Focuses light rays onto the retina 

What is the function of the retina?

Converts light into electrical signals to perceive images 

What is the function of the ciliary body?

Produces aqueous humor which nourishes the eye and helps focus light 

What is the function of the iris?

Controls the amount of light entering the eye

What is the function of the pupil?

Regulates the amount of light entering the eye 

What is the function of the optic disc?

The optic nerve exits containing photoreceptors

What is the function of the fatty cushion?

Provides support and protection 

Understand how light travels to the back of the retina and is processed through the rods and cones. (15.3)

• Light enters the eye- Through the cornea and pupil then light is focused onto the retina

• Photoreceptor activation- Light hit the photoreceptor in the retina which causes them to convert light into electrical signals 

• Phototransduction-  initiate a biochemical process that converts light into electrical signals that then get sent to the brain

• Signal transmission- The electrical signals travel through the optic nerve to the brain where they are interpreted as images 

• Visual Perception- The brain processes these signals to create the perception of visual images

What is the visual perception of cones?

• Sensitive to low light levels and are primarily responsible for night vision and peripheral vision. 

• They do not perceive color only black and white

What is the visual perception of rods?

• Sensitive to bright light levels and are responsible for color vision

•  Provide high spatial acuity and can differentiate different colors

What is the retinal Localization of rods?

Located in the periphery of the retina 

What is the retinal Localization of cones?

Located in the central fovea (crucial for high acuity vision)

Describe the visual pathway from light passing through cornea to occipital lobe (15.4)

• Light enters the eye- Through the corneas, pupil, and lens which focus light onto the retina 

• Photoreceptors convert light into signals- the retina contains rods and cones which detect light and convert into electrical signals 

• Signals are transmitted- the optic never carries these signals from the retina to the brain 

• Information is processed- the brain visual cortex interprets the visual information to form images and perception