Special Senses Flashcards

Fill-in-the-blank flashcards covering key concepts of vision, hearing, vestibular function, olfaction, and gustation from the lecture notes.

The nerve that carries visual information from the eye to the brain is __.

CN II (Optic nerve)

The transparent layer that bends light entering the eye to help focus on the retina is the __.

Cornea

The colored part of the eye that surrounds the pupil and controls pupil size is the __.

Iris

The outer protective layer that allows attachment of the extrinsic eye muscles is the __.

Sclera

The outermost tunic of the eye is called the __, which includes the sclera and cornea.

Fibrous tunic

The layer covered externally by the conjunctiva is the __.

Sclera

Pupillary constriction occurs when the circular muscles of the iris contract under __ stimulation.

parasympathetic

Pupillary dilation occurs when the radial muscles of the iris contract under __ stimulation.

sympathetic

The two photoreceptor types are and .

Rods and cones

Rods function well in __ light and do not see color.

low

Cones provide color vision and there are __ different types.

3

The image on the retina is upside down and __.

back to front

The process by which the lens changes shape to focus the image on the retina is called __.

Accommodation

Phototransduction results in a change in the rate of neurotransmitter release from the photoreceptors; in light, this release is __.

reduced (decreased)

In darkness, CGMP-gated Na+ channels are open, creating the __.

dark current

In darkness, glutamate release at the photoreceptor terminals inhibits __ cells.

bipolar

The partial cross of visual information occurs at the __.

optic chiasm

The outer, middle, and inner ear are the three regions of the ear; the ear contains the cochlea.

inner

The three auditory ossicles are the malleus, incus, and __.

stapes

The opening that connects the middle ear to the nasopharynx is the __ tube.

Eustachian (auditory) tube

The stapes sets up vibration in the __ window.

oval

The Organ of Corti sits on the __ membrane.

basilar

The three cochlear ducts are the scala vestibuli, scala media, and scala __.

tympani (tympanic)

The hair cells of the Organ of Corti are the sensory receptors for the sense of __.

hearing

High-pitched sounds distort closer to the __ window.

oval

Volume is coded by the degree of distortion of hair cells; higher amplitude means __.

louder

The ampulla is the swollen region at the base of each canal.

semicircular

Higher-level processing of vestibular information occurs in the vestibular area of the .

cerebral cortex

Olfactory receptor cells are a type of neuron.

bipolar

Olfactory receptor cells express a single protein.

receptor

All receptor cells expressing a specific receptor protein gene project to the same .

glomerulus

Odorant binds to a -protein coupled receptor.

G

Olfactory information is processed in the primary olfactory area of the lobe.

temporal

There are five primary tastes: sweet, sour, salty, bitter, and .

umami

Taste buds contain gustatory receptor cells, supporting cells, and cells.

basal stem (basal) cells

Salt tastes involve sodium ions entering through channels.

sodium (Na+) ion channels

Bitter tastes involve about receptors.

30

Gustatory information travels via cranial nerves , IX, and X to the gustatory nucleus, then to the primary gustatory area.

VII