A&P Ch 11 The Sensory System

Nerve impulses are carried from the ear to the brain by the _______ nerve

vestibulocochlear

maculae and cristae

Maculae are vestibular receptors used to detect acceleration. Cristae are semicircular canal receptors used to detect rotation.

Which eye structure has the greatest effect on light refraction?

cornea

Increased pressure inside the eyeball

glaucoma

Which nerve carries sensory signals from the retina to the brain?

optic

The part of the nervous system that detects a stimulus is a

receptor

The bending of light rays as they pass from one substance to another is called

refraction

Irregularity in the curvature of the cornea or lens

astigmatism

special sense and general sense

A special sense is localized in a special sense organ, whereas a general sense is widely distributed throughout the body.

Compare and contrast conductive hearing loss and sensorineural hearing loss

Conductive hearing loss is caused by damage to ear structures that transmit sound waves from the outside to the inner ear (e.g., tympanic membrane). Sensorineural hearing loss is caused by damage to ear structures that sense, transmit, or interpret sound (e.g., cochlea, spiral organ, vestibulocochlear nerve, and brain). Evan's hearing loss was sensorineural. It was caused by his immune response to an organism that caused bacterial meningitis and/or the drugs used to treat the infection resulting in damage to his auditory receptor cells.

endolymph and perilymph

Endolymph is a fluid found in the ear's membranous labyrinth. Perilymph is a fluid found in the ear's bony labyrinth.

Trace the pathway of a nerve impulse from the olfactory receptors to the olfactory center in the brain

Nerve impulses from the olfactory receptors are carried by the olfactory nerve to the olfactory center in the temporal lobe.

rods and cones

Rods are retinal receptor cells used for vision in dim light. Cones are retinal receptor cells used for color vision in bright light.

Name several types of pain relieving drugs. Describe methods for reliving pain that do not involve drugs.

Some pain-relieving drugs are NSAIDs (nonsteroidal antiinflammatory drugs), narcotics, and anesthetics. Other pain-relieving methods include massage, acupressure, electrical stimulation, application of heat and cold, and relaxation techniques.

extrinsic and intrinsic eye muscles

The extrinsic eye muscles are attached to the surface of the eye and move the eyeball. The intrinsic muscles are within the eye. They are the ciliary muscle, which controls the shape of the lens for accommodation, and the iris, the pigmented ring of muscles that regulates the amount of light entering the eye.

name 5 basic tastes. Where are the taste receptors. Name the nerves of taste.

The five basic tastes (sweet, salty, sour, bitter, and umami) are detected by taste receptors (taste buds) located on the surface of the tongue. The facial (VII) and glossopharyngeal (IX) cranial nerves transmit the sensation of taste to the brain.

Trace the path of light ray from the outside of the eye to the retina

The pathway of light from the outside of the eye to the retina is cornea, aqueous humor, lens, vitreous body, and retina.

List in order the structures that sound waves pass through in traveling through the ear to the receptors for hearing

The pathway of sound waves through the ear to the receptors of hearing involves the following structures: external auditory canal, tympanic membrane, malleus, incus, stapes, oval window, perilymph (vestibular duct), endolymph (cochlear duct), hair cells and tectorial membrane, perilymph (tympanic duct), and round window.

define convergence and accommodation & several disorders associated with them

The process of convergence centers both eyes on the same visual field. An inability to converge the eyes is called strabismus. The process of accommodation allows the eye's lens to focus on near or far objects. As we age, the lens becomes less elastic and less able to accommodate, a condition called presbyopia.

What do receptors in the vestibule sense?

acceleration

Loss of vision in a health eye because it cannot work properly with the other eye

amblyopia

From superficial to deep, what is the order of the eyeball's tunics?

fibrous, vascular, nervous

Progressive loss of near accommodation ability with age

presbyopia

A receptor that senses body position is a

proprioceptor

A receptor's loss of sensitivity to a continuous stimulus is called _______

sensory adaptation

Deviation of the eye due to lack of coordination of the eyeball musles

strabismus

Which of the following is a general sense?

touch

How would you explain the role of hair cells in hearing and how the cochlear implant can overcome their loss?

•The receptors for hearing are hair cells located along the cochlear duct in the inner ear. •The cells are stimulated by sound waves traveling through the inner ear. •The vibrations cause movement of the cells, generating nerve impulses that are transmitted to the brain via the vestibulocochlear nerve. •A cochlear implant transmits sound frequencies directly to the cochlear nerve, bypassing the damaged receptor cells.

which disorder involves the tympanic membrane is red and bulging outward toward the external auditory canal?

•The red, bulging tympanic membrane indicates that Maria has otitis media, which is common in children because of their relatively short and horizontal auditory tube. •Treatment options include antibiotics, myringotomy, and placement of a tympanostomy tube.

How can you explain a ride at the fair affects balance?

•The roller coaster ride has affected your friend's rotational equilibrium by putting in motion the fluid inside of her semicircular canals. •For a short time after the ride, the fluid continues to move, sending a message to your friend's brain that she is still in motion, thus affecting her balance.