vision and the eye Flashcards
what is the stimulus for vision?
electromagnetic energy or light waves
what is the lens?
elastic structure that changes to help focus
when the lens becomes thinner, it is focusing on objects that are?
far away/more distant
what is the retina?
a multi-layered structure at the back of the eye that contains light-sensitive photoreceptors
what is the function of the retina?
light-sensitive photoreceptors transduce light into electrical impulses
what is the cornea?
transparent protective structure at the front of the eye
what is the pupil?
and adjustable opening behind the cornea
what is the function of the pupil?
controls the amount of light that enters the eye through iris muscles
when pupils dilate, they? when pupils constrict, they?
get bigger; get smaller
what does your ability to see clearly depend on?
being able to accurately focus an image directly into your retina
what is myopia? people with myopia have difficulty seeing?
nearsightedness; difficulty seeing far away objects
what is hyperopia? people with hyperopia have difficulty seeing?
farsightedness; difficulty seeing up close objects
what are the two types of light sensitive cells found in the retina?
rods and cones
what are rods?
photoreceptors that contribute to black and white vision and are more sensitive to light then cones
what is the fovea?
the center of the retina that increases in concentration through the periphery of the retina