The Eye and Vision Flashcards
Eyes are surrounded by _________ ______:
Protective Tissue
The amount of light entering the eye is monitored by the ____:
Iris
TRUE OR FALSE: If someone is missing one type of cone they are color blind
True
Nearly __% of all the sensory receptors in your whole body are in the eyes
70%
What is another name for Nearightedness?
Myopia
Define Nearsightedness:
The point of focus falls in a spot in front of the Retina. Eye is too long and/or cornea is too steep.
What is another name for Farsightedness:
Hyperopia
Eyes are surrounded by _________ _____:
Protective Tissue
The round walls around your eyes have 3 layers:
The Sclera, The Retina, and a middle layer that provides a rich blood supply
Light enters through the “clear window” in the sclera
Cornea
The amount of light entering the eye is monitored by the ____:
Iris
How long is each eyeball?
Each eyeball is about an inch in diameter
Can the cornea heal itself fast or slowly? If so how long does it take to heal ?
The Cornea heals itself fast, it takes one to two days
Does the Cornea have blood supply?
No
The Iris is made up of involuntary muscles that adjust the size of the pupil based on how much _____ __ ______ __ :
Light is coming in
The Retina contains _____________ _____:
Photoreceptors cells
Rods:
See dim light, gray tones , and motion
Cones:
There are 3 types of cones each sensitive to a range of color
What do eyeglasses do:
Can adjust how the light is bent when it enters your eyes
What lens corrects nearsightedness:
Concave Lens
What lens corrects farsightedness:
Convex lens
FUN FACT <3:
Lenses of different shapes will bend the light to different degrees so the point of focus falls on the Retina
We have photoreceptors over out entire Retina except in out ____ ____:
Blind Spot
Blind Spot:
Is where the optic nerve leaves the eyeball, carrying signals to the occipital lobe
TRUE OR FALSE: When light passes through the lens, it is bent by the lens and focused on the Retina
True
The ____ focuses light entering the eye on the Retina:
Lens
The muscles in the Iris do what to the pupil:
Contract and expand changing the size of the dark dot of your pupil
Pupil:
The opening in the Iris that allows light to travel into the eye
Iris:
Distinctive colored part of the eye that is uniquely yours and is made up of smooth muscles
The eyes Photoreceptors:
Convert light energy into nerve impulses that the brain can understand
Light:
Electromagnetic radiation traveling in waves
Photoreceptors send signals to the brain through the _____ ____:
Optic Nerve
