Chapter 8- Special Senses

Emmetropia eye

________ focuses images correctly on the retina.

Impulses

________ are transmitted via the olfactory filaments to the olfactory nerve (I)

Lens

________ divides the eye into two chambers.

Menieres

________ affects inner ear and causes progressive deafness and perhaps vertigo (sensation of spinning)

Iris

________- regulates amount of light entering eye.

Choroid

________ is a blood- rich nutritive layer that contains a pigment (prevents light from scattering) & is modified anteriorly into two smooth muscle structures.

Synapse

________ with neurons in the thalamus- (relaying of sensory signals, including motor signals, to the cerebral cortex, and the regulation of consciousness, sleep, and alertness)

newborn infant

The ________ can hear sounds, but initial responses are reflexive.

Lens

________ divides the eye into two chambers.

Accommodation the lens

________ must change shape to focus on closer objects (less than 20 feet away)

Equalizes pressure

________ in the middle ear cavity so the eardrum can vibrate.

Maternal infections

________ during the first 5 or 6 weeks of pregnancy may cause visual abnormalities as well as sensorineural deafness in the developing child.

Taste

________ and smell are most acute at birth and decrease in sensitivity after age 40 as the number of olfactory and gustatory receptors decreases.

Fovea centralis

________- lateral to blind spot.

Hair cells

________ are stimulated, impulse travels vestibular n. to the cerebellum.

Humors

________ are fluids that fill the interior of the eyeball.

poor visual acuity

The infant has ________ (is farsighted) and lacks color vision and depth perception at birth.

Tarsal

________ glands produce an oily secretion that lubricates the eye.

Presbycusis type of sensorineural deafness

________ that may result from otosclerosis (ear ossicles fuse)

Pressure waves

________ cause vibrations in the basilar membrane in the organ of Corti.

Gel

________- like tectorial membrane is capable of bending hair cells.

Sound

________ is amplified by the ossicles.

Smell

________ can differentiate a wider range of chemicals.

Convergence

________: reflexive movement of the eyes medially when we focus on a close object.

cornea

Light is bent, or refracted, by the ________, aqueous humor, lens, and vitreous humor.

Membranous labyrinth

________ is suspended in perilymph and contains endolymph.

Taste buds

________ are replaced frequently by basal cells.

External ear

________ is involved only in collecting sound waves.

Sweet receptors

________ respond to sugars, saccharine, some amino acids.

Presbyopia old vision results

________ from decreasing lens elasticity that accompanies aging.