Chapter 15 Special Senses A&P 2

Aqueous humor forms during capillary filtration in the __________?

ciliary body

A nurse is administering Pilocarpine eye drops. The nurse instructs the patient to press on the nasolacrimal duct for 30 seconds because the medication can have some systemic side effects, such as affecting the heart rate. What is the rationale for pressing on the nasolacrimal duct?

Applying gentle pressure to the nasolacrimal duct prevents the delivery of the drug to the nasal mucosa and general circulation, where it could affect heart rate

A nurse is administering Pilocarpine eye drops. The nurse instructs the patient to press on the nasolacrimal duct for 30 seconds because the medication can have some systemic side effects, such as affecting the heart rate. What is the rationale for pressing on the nasolacrimal duct? `

Applying gentle pressure to the nasolacrimal duct prevents the delivery of the drug to the nasal mucosa and general circulation, where it could affect heart rate.

Fovea Centralis

Area of greatest visual acuity

True or False The bony labyrinth of the inner ear is housed in the parietal bone of the skull

False

True or False The structure that allows equalization of the pressure in the middle ear with that outside the body is the external auditory meatus.

False

True or False, The structure that allows equalization of the pressure in the middle ear with that outside the body is the external auditory meatus

False

Which structures involved in detection of BOTH hearing and equilibrium?

Inner Ear

What structure regulates the amount of light passing the visual receptors of the eye?

Iris

The white, dense connective tissue covering of the eye is the

Sclera

Baby Mary's pediatrician notices that one of her eyes rotates outward and that she does not appear to be using it for vision. He calls it "lazy eye". What is her condition, and what does the pediatrician recommend?

She has strabismus. The doctor's recommendations are for eye exercises and/or placing a patch over the unaffected eye; in severe cases, the condition may require surgery.

Nutrients are delivered and waste products are carried away from the cells of the posterior segment of the eye by blood vessels. However, the cornea and lens (in the anterior segment) are avascular. Which is the best explanation for how their cells are maintained?

The aqueous humor is a blood filtrate produced by the ciliary process, and it nourishes these cells.

Roger went for his yearly eye examination and was informed that his intraocular pressure was slightly elevated (at 22 mm Hg). The physician expressed concern over this condition and noted that if the condition got worse, eyedrops would be merited. What is wrong with Roger's eyes? What are the possible consequences of this condition? What is the function of the eyedrops?

The condition is glaucoma. Blindness could result if not treated or caught early. The eyedrops increase the rate of aqueous humor drainage or decrease its production

Identify the type of neuronal cell that detects bright light and provides high-resolution color vision.

The cone cells

True or False Rods have a convergent wiring pattern to the ganglion cells, causing blurry images.

True

True or False The sensory receptor cells for equilibrium are mechanoreceptors

True

True or False, Without functioning cristae ampullares, the semicircular ducts would not function

True

The blind spot of the eye is caused by ________.

a lack of photoreceptors where the optic nerve leaves the eye

The ability of the lens to increase its curvature for near vision is called

accomodation

Its fibers resonate to different frequencies along its length:

basilar membrane

The hair cells of the spiral organ of Corti are arranged in rows on the

basilar membrane

Aqueous humor forms during capillary filtration in the___?

ciliary body

Which structure is NOT matched with its function?

ciliary body: controls the size of the pupil

Receptors for hearing are located in the ________.

cochlea

Receptors for hearing are located in the____.

cochlea

Congenital sensorineural deafness would be expected to involve damage to ______.

cochlear hair cells or cochlear nerve

Otitis media is often accompanied by pain and some

conduction deafness

Someone whose eyes appear red and inflamed is suffering from

conjunctivitis

Someone whose eyes appear red and inflammed is suffering from

conjunctivitis

There are two tiny skeletal muscles within the middle ear cavity. They function to

dampen ossicle movement to prevent cochlear damage from loud sounds

Mrs. Alvarez is a 70 year old woman who is visiting an eye doctor because of poor vision. She has a history of osteoporosis, diabetes, and hypertension. The eye doctor examines her retina and notes that there is an excessive overgrowth of retinal blood vessels. This patient is suffering from _________, caused by _______.

diabetic retinopathy; hyperglycemic damage to blood vessels

Choose the two variables which are used by the auditory cortex to localize the source of sounds around us:

differential time of arrival at two ears, differential intensity of sounds at two ears

The pupils _________ in dim light and __________ in bright light.

dilate; constrict

The transmission of sound waves through the inner ear occurs chiefly through

fluid

The retinal area that provides the greatest visual acuity when light is focused there:

fovea centralis

Aqueous humor

helps maintain the intraocular pressure; located in the anterior part of the eye

Which of the following is a possible cause of conduction deafness?

impacted cerumen, otitis media, and perforated or scarred tympanic membrane

Where are equilibrium receptors located?

in the semicircular canals and in the vestibule of the ear

The lens thickens and its elasticity decreases with age. This leads to which of the following?

inability of the lens to accommodate for near vision

A person whose right eye was removed because of a tumor will experience

loss of depth perception and blindness in the far right side of the visual field

A person whose right eye was removed because of a tumor will experience:

loss of depth perception and blindness in the far right side of the visual field.

A condition in which the pigmented epithelium degenerates in the macular region of the retina, leading to loss of photoreceptors and central vision, is called

macular degeneration

Which of the following is the best explanation for why night vision is fuzzy and indistinct?

many rods provide input into each ganglion cell, so their input is summed

Ear structures that amplify the motion of sound waves include

middle ear ossicles

Which of the following is not a good explanation of why it is difficult to discriminate the color of an object at night?

only cones have a 1:1 wiring arrangement with ganglion cells

Which are the correct changes that occur when a person looks at something close-up?

pupils constrict, lens becomes more convex, eyeballs converge

The ciliary muscles of the eye are

responsible for controlling the shape of the lens

The receptor organ for hearing is the _____

spiral organ of Corti

Which middle ear ossicle is attached to, and transmits vibratory motion to, the oval window?

stapes

In the organ of Corti, the stereocilia (hairs) of receptor cells are embedded in a gelatinous structure called the

tectorial membrane

Information from equilibrium receptors is processed, interpreted and acted on in __________.

the brain stem and cerebellum

Retina

the sensory layer of the eye

Lens

the structure most responsible for focusing light rays that enter the eye

Damage to the left primary visual cortex, as from a stroke, will have this effect:

vision will be lost in the right half of the visual field

Depth perception is provided by

visual input from both eyes, extensive overlap in the visual fields of the two eyes, crossing over of half the axons from each retina at the optic chiasma