Unit 1.2 Eye See You Flashcards
What is the first structure that light encounters when entering the eye?
The cornea.
After the cornea, where does light pass through next?
The aqueous humor, then through the pupil, where light enters the eye.
What controls the size of the pupil?
The iris.
What is the role of the crystalline lens in the eye?
The crystalline lens focuses light onto the retina by changing its shape through the action of the ciliary muscles.
What is the vitreous humor?
The transparent fluid fills the vitreous chamber in the posterior part of the eye, maintaining its shape.
What is the retina’s function?
The retina is a light-sensitive membrane that receives the image from the lens and converts it into neural signals through photoreceptors (rods and cones).
How does light transduction occur in the retina?
Light is detected by photoreceptors (rods and cones), which transduce the light energy into neural signals processed by bipolar cells and then sent to ganglion cells.
What is the tapetum?
a reflecting surface in the back of the eye that reflects the light back through the retina one more time. (found in nocturnal animals)
What is the process of accommodation in the eye?
Accommodation is the adjustment of the lens shape to focus on near or far objects, controlled by the ciliary muscles.
Why is refraction necessary?
to focus light rays and this is done by the cornea and the lens
What is emmetropia?
the condition of having normal vision without any refractive error, meaning light is focused correctly on the retina.
What is myopia?
Myopia, or nearsightedness, occurs when light entering the eye is focused in front of the retina, making distant objects appear blurry. It is often caused by an elongated eyeball.
How can myopia be corrected?
Myopia can be corrected with glasses that have concave lenses or through laser surgery that reshapes the cornea to adjust the refractive power.
What is hyperopia?
Hyperopia, or farsightedness, occurs when light entering the eye is focused behind the retina, resulting in difficulty seeing nearby objects clearly.
How is hyperopia corrected?
Hyperopia can be corrected with glasses that have convex lenses, which help focus light onto the retina.