Science Section 3 - additional Flashcards
What is the vestibular system?
the sensory system comprised of components in the inner ear that provides the brain with information about motion and position; creates the sense of balance and spatial orientation
Sensory transduction
process of translating light, sound, or pressure into electrochemical signals
What is proprioception?
the sense of where your body is in a space
Receptive field
region where a sensory receptor can detect a stimulus (specific to each sensory receptor)
What is the retina?
the thin layer at the back of the eyeball where there are rods and cones for phototransduction to take place
Cornea
the front, transparent layer of the eye where refraction of light takes place
What is refraction?
bending or focusing
What is the iris?
the circular, pigmented muscle that controls the size of the pupil in the eye
When does the pupil/iris dilate?
in dim or low light
When does the pupil/iris contract to reduce its size?
in bright lights
What is the function of the lens in the eye?
further refracts light to focus the image on the retina by changing its shape
Reduction to the len’s flexibility becaues of aging causes what?
farsightedness
What is myopia?
Nearsightedness; occurs when the distance between the retina and cornea is too long so the image focus falls in front of the retina
Function of photoreceptors
to receive and transduce light in the retina
Pigmented epithelium
a pigmented cell layer just outside the retina that works to support the function of photoreceptors, for example, by absorbing excess light and getting rid of broken photoreceptor cells
What is the choroid?
network of blood vessels outside the pigmented epithelium layer that brings oxygen and nutrients to the photoreceptor cells
Fovea
center of the retina where vision is the most acute or sharpest
Function of rods
used for peripheral and low light vision as they have more disks and are located outside of the center of the retina
Function of cones
Respond to bright lights and are located in the fovea
What are opsins?
pigments that absorb different wavelengths of color
What type of opsins do rods use?
rhodopsin
Short waves of light are usually what color?
blue
Medium wavelengths of light are usually what color?
green
Long wavelengths of light are usually what color?
red