The Eyes: Visual Sense Flashcards
Shape of the eyes
Ball-shaped
Power to react to the stimuli
Sensibility
The ability to conduct and transport messages
Conductivity
Capacity to react to certain stimuli
Specificity
Capability to be used to a particular stimuli
Adaptability
Where the eyes is found
Eye socket
A transparent protective window that is constantly washed by tears making it always clean
Cornea
Where the rays of light travel first
Cornea
Colored part of the eyes
Iris
At the middle of the iris is dark hole called ______ also it is where the light enters
Pupil
Once light passes through the pupil it enters the _____ which is located behind the pupil
Lens
The lens active entries of light to focus them on the _____
Retina
Is the part of the eyes that changes electromagnetic energy of light into useful information for the brain
Retina
A thin layer of nerve cells at the back of the eyeball
Retina
Two types of light sensitive receptor cells in the retina
Rods & cones
Responsible for a twilight vision or light of low intensity; long and cylindrical
Rods
Responsible for daylight vision and colors; short, thick and tapered
Cones
The center of the retina is the ______ which is the point of the clearest vision in the daylight; very sensitive region of the retina
Fovea centralis
It starts a chain of events which transform light into neural impulses that communicate to the brain through _____
Optic nerve
The optic nerve is a bundle of ________ cells at the back of the eyeball
Ganglion
It collect and summarize visual information which are gathered and move out of the back of the eyeball
Ganglion cells
It is a bundle of ganglion axons
Optic nerve
A point between and behind the eyes wherein the more impulses from the optic nerve are reversed in the brain
Optic chasm
People who find difficulty in seeing a light or object at night are called
Night - blind
Night blindness results from deficiency in the pigmentation layer in the retina which supplies
Rhodopsin
Caused by ABNORMAL LONG EYEBALL so that the image is focused in front of the retina; can see the near objects.
Myopia or Nearsightedness
Myopia or Nearsightedness have to wear eyeglasses with _____
Concave lenses
when the EYEBALL IS SO SHORT dati image is focused behind the retina; can see clearly at a far distance
Hyperopia or Farsightedness
Hyperopia or Farsightedness have to wear eyeglasses with ____
Convex lenses
Farsightedness of OLD AGE which is caused by the SLOW HARDENING of the lens
Presbyopia
Caused by the UNEVEN CURVATURE of the cornea
Astigmatism
Is congenital farsightedness or defect in the eye muscles; have an equal vision in the two eyes
Cross-eye
Cross eye can be corrected before the child turns ____
6 yrs old
Caused by a CONCENTRIC NARROWING of the field of vision so that a person seems to be looking through a channel or pipe
Tunnel vision
Caused by a muscular imbalance which permits light to be reflected from one point to fall on non-responding receptors in the two retina so that two different images are transmitted to the brain
Diplopia or double vision
Resulting from excessive use of tobacco or alcohol or from over exposure to light producing temporary or permanent blindspot interfering with vision
Scoma
A rapid involuntary side movement of the eyeball or optic nystagmus
Albinism
The lens of the eyes changes from clear transparent structure to a cloudy or opaque eyes
Cataract
Cause of new cases of blindness characterized by hemorrhaging of the tiny vessels of the retina as a result vision is blurred or distorted
Diabetic retinopathy
Part of the eyes that give them color
Iris
