Eye Flashcards
1
Q
Aqueous Humor
A
- clear, watery fluid found in the anterior chamber of the eye
2
Q
Pupil
A
- hole in the center of the eye where light passes through the eye
3
Q
Cornea
A
- the transparent tissue that covers the front of the eye
- no blood vessels, but has nerves
4
Q
Iris
A
- circular band of muscles that control the size of the pupil and give color to the eyes
5
Q
Lens
A
- the transparent part that bends light passing through
6
Q
Vitreous Humor
A
- clear, jelly fluid that is located in the back portion of the eye and helps maintain the shape of the eye
7
Q
Sclera
A
- protective coating on the back of the eye
8
Q
Tapetum
A
- it reflects visible back through the retina and increases the light available to light receptors
9
Q
Optic Nerve
A
- transmits electric impulses from the retina to the brain
- impulses from rods and cones passtrhough nerve cells
10
Q
Blind Spot
A
- where the retina connects
- no images can be detected
11
Q
Photoreceptors
A
- two special types of nerve cells:
- rods and cones
12
Q
Rods
A
- function in dim light
- perceive shades of gray
13
Q
Cones
A
- function in bright light
- provides sharp, colorful images
14
Q
Types of Cones
A
- work together to interpret more than just red, green, and blue
- each type is sensitive to a different range of wavelengths of light
15
Q
Malfunction in Cones
A
- color defeciency
- color blindness
16
Q
Death Perception
A
- ability to judge the relative distance between objects in 3-D
- one eye: field of vision appears 2-D
- two eyes: eyes see and brain processes different views of the same object
17
Q
Accomodation
A
- cornea and lens focus light on the retina
- combination of reflex actions by which the lens of the eye changed to keep the focal length distance between the center of the lens and its focal constant
18
Q
Cornea and Lens Accomodation
A
- cornea does most work but cannot change shape
- fine adjustments are carried out by the lens
19
Q
Astigmatism
A
- lens or cornea is iregularly shaped which causes incoming light rays to reflecct and converge improperly because they don’t focus on a specific point on the retina
- results in a blurry or disorted image
20
Q
Correcting Astigmatism
A
- eyeglasses, contacts, refractive surgery
21
Q
Blind Spot
A
- optic nerve exits eye at retina to brain
- no receptors that respond to light = image there can’t be seen
- brain ignores hole - eyes are always on the move
22
Q
Peripheral Vision
A
- ability to see things outside the direct line of vision
- rods are responsible because of proximity to edge of retina
- better for detecting movement than processing sharp images
- stronger in the dark
23
Q
Optical Illusions
A
- visual tricks
- visual cortex of the brain deciphers images sent from the eye however surrounding objects, intesnse colors, distortions of expected patters and preconceptions can cause the mind to see and interpret an image differently
24
Q
Afterimages
A
- optical illusions that occur when looking away after intently looking at a fixed imageor colri
- constant light stimulates the retina which causes cones to become fatigued
- less-stimulated cones aren’t fatigued so they still function and produce negative images
25
Retina
- tissue located on the back of the eye that contains photoreceptors that are responsive to light
- possesses two types of nerve cells called photoreceptors