Scioly - Sense Organs

iris

a colored sheet of muscle that controls the arount of light entering the eye by changing the size of the pupil

cornea

a clear area of the sclera that helps to bend light into the retina

aqueous humor

a fluid filling the front of the eye that helps bend light into the retina and supplies nutrients/oxygen to the lens

conjunctiva

a thin clear protective layer over the surface of the eye that lines the eyelids

ciliary muscles

they change the shape of the lens; when contracted, they make the lens thicker for nearer focus

vitreous humor

a clear gel that helps maintain the shape of the eyeball and bend light into the retina

retina

a layer of light-sensitive cells that send impulses to the optic nerve

fovea

a small area of the retina responsible for sharpest vision, containing only cone cells

tapetum

a blue retroreflective layer behind the retina that enhances night vision in animals

pathway of light through the eye

light travels through the cornea, aqueous humor, pupil, lens, vireous humor, and finally reaches the retina

rods

responsible for detecting brightness and motion (in the retina)

cones

responsible for detecting color and fine details (in the retina)

bipolar cells in the retina

transmit information from photoreceptors to ganglion cells

optic chiasm

nasal fibers cross, affecting the peripheral vision and potentially causing bitemporal hemianopia

outer hair cells

amplify low-level sounds, these are in the cochlea

lateral geniculate nucleus (LGN)

organizes and relays visual information from the optic tract to the visual cortex

cochlea

a spiral-shaped structure that conducts vibrations through fluid and is essential for hearing

ossicles

malleus (hammer), incus (anvil), and stapes (stirrup), which amplify and transmit sound waves

olfactory epithelium

contain olfactory receptor cells that detect ordorants

path of smell from nasal cavity to the brain

odorants bind to receptors in the olfactory epithelium, activating G-proteins which send signals through the olfactory nerve to the olfactory bulb and then to the brain.

primary tastes detected by the taste buds

sweet, sour, salty, bitter, and umami

gustatory nerves

transmit taste signals from the tongue to the brain

semicircular canals

detect head movement and help maintain balance and spatial orientation

vestibulocochlear nerve

carries auditory information from the cochlea to the brain

Organ of Corti

contains hair cells that transduce sound vibration into neural signals

inner hair cells

transmit sound information to the auditory nerve, these are in the cochlea

primary visual cortex

responsible for the initial processing of visual information from the retina

tonotopic organization

refers to the spatial arrangement of hair cells in the cochlea that corresponds to different sound frequencies