Eye
To correct hyperopia, is it necessary to move the image formed by the eye closer or farther away from the eye's lens system? Does this require a convergent or divergent lens?
Bring it closer, convergent is required
Does a far-sighted person have trouble seeing distant objects? Why was it not necessary to change the lens to look far away?
No because it is behind the retina
Why don't we see things upside down?
The brain flips it (the occipital lobe)
Left to right traffic lights might cause problems for a driver with red-green perception deficiency because?
The colors would blend together so they would not know when to go or stop
Astigmatism Definition
vision condition that causes blurred vision due to cornea being irregularly shaped
Depth Perception Definition
visual ability to percieve world in 3D and distance
Cornea Function
acts as the eyes outermost lens. functions like a window that controls and focuses the entry of light into eye
Refraction
bending of light that occurs in the eye
Blind Spot Function
carries images to the brain
Cones definition
cell in retina that are responsible for color vision and ability to see in bright light
Lens Function
changes the focal distance of the eye so that it can focus on objects at various distances
Pupil Function
controls the amount of light that gets into the eye
Iris Function
controls the diameter and size or pupil and amount of light reaching retina
Hyperopia Definition
farsightedness; blurry close vision
Viterous Humor Fuction
helps mold sperical shape
Sclera Function
helps to maintain the shape of the eyeball and provides an attachment point for the extrinsic eye muscles
Myopia Definition
nearsightedness; blurry distance vision
Aqueous Humor Function
nourishing cornea and the lens by providing nutrition maintin intraolular pressure
Accommodation definition
process when eye changes to maintain clear focus on object or imagine
Retina Function
receive light that the lens has focused, convert the light into neural signals, and send these signals on to the brain for visual recognition
Function of the Ciliary Muscle
relaxes or tightens the zonules to enable the lens to change shape for focusing
Tapetum Function
retroflector which reflects light directly back along the light path
What is accommodation in the eye? How are muscles involved in this process?
Accomidation is the process when the eye changes focal lenght to maintain focus on objects or images. The muscle that changes is the ciliary muscle that changes the focal length
Why is the near point closer for a myopic person than that of a hyperopic person?
Because myopic people are near sighted and can see things better up close and hyperopic people are far sighted.
Explain what happens in the eye to cause an afterimage
Cones are fatigued so less cones means you see different colors.
Explain the specific roles of rods and cones in the eye
Cones- color and sharpness/brightness Rods- side vision and dark colors (blacks,grays, and whites)
List several careers or activities in which depth perception plays an important role.
Driving and swimming
What can you infer about the development of color perception deficiency?
It is sex-linked trait (on X chromosomes)
What happens to the clarity of the image when you decrease the pupil size? How does this relate to squinting?
It sharpens due to less light in the eye just like what happens when you squint bcause youre covering your pupil more and more causing sharpness
Explain the importance of the fovea centrails
The fovea centralis is important for sharp/clear vision. You need it for writing/reading and watching tv
What is happening in the eye to caue astigmatism, and how does impact how you see?
The lens is irregularly shapes causing light to refract all over the eye causing blurry and bolded lines
If we have three different types of cones - red cones, blue cones, and green cones - how do we see such a wide range of colors?
They blend together to make more colors
Describe what needed to occur for the distant object to be in focus. How does this relate to what actually happens in the human eye?
When you squint the lens changes shape which allows for less light to come in which sharpens the image
Optic Nerve Function
transfer visual information from the retina to the vision centers of the brain via electrical impulses
Rods definition
type of specialized light sensitive cell in the retina of the eye that provides side vision and ability to see dim light
What structure in the eye does the water represent? Explain the function of this liquid.
ultrasis->nutritious itaqueous-> keeps it in place