Chapter 16: Eye and Ear

What structures do tears travel through?

-Lacrimal puncta -Lacrimal canaliculus -Lacrimal sac -Nasolacrimal duct

What are the names of the cochlea's 3 fluid filled ducts?

-Scala tympani -Cochlear duct -Scala vestibuli

Sensory receptors in which structures help monitor and adjust our equilibrium?

-Semicircular ducts -Saccule -Utricle

Optic tracts extend to which structures after they leave the optic chiasm?

-Superior colliculi -Lateral geniculate nucleus of the thalamus

Each macula of the utricle and saccule is composed of which structures?

-Supporting cells -Hair cells

Order the following structures from superficial to deep: -Neural layer of the retina -Choroid -Pigmented layer of the retina -Sclera

1) Sclera 2) Choroid 3) Pigmented layer of retina 4) Neural layer of retina

How many extrinsic eye muscles are responsible for each eye?

6

What type of fluid is found in the anterior cavity?

Aqueuos humor

Pupils contricting, cones gradually adjusting, and rods becoming inactive all occur during what adaptation?

Bright light adaptation

The optic disc is associated with what cranial nerve?

CN II

The point of greatest visual acuity in the retina is where?

Central Fovea

Vestibular nerve axons project first to which structures?

Cerebellum and medulla

Which structure within the ampulla contains hair cells that are involved in dynamic equilibrium?

Crista

Which of the following structures senses change in rotational acceleration of the head in order to help maintain dynamic equilibrium?

Cupula

Earwax is a combination of what two things?

Dead skin cells Cerumen

The auricle has what type of cartilage that supports its structure?

Elastic

The auricle directs sound waves into the bony tube called what?

External acoustic meatus

Myopia

Eyeball is too long

Hyperopia

Eyeball is too short

What cannels in the photoreceptor open as a consequence of the dark current?

Glutamate

Which structure transduces mechanical vibration into electrical signals?

Hair cells

The [OUTER/INNER] segment of the photoreceptors connect directly to the cell body.

Inner

Cataracts are a disorder of what part of the eye?

Lens

Lacrimal fluid prevents bacterial infection because it contains an antibacterial enzyme called what?

Lysozyme

Which ear structure contains otoliths (ear stones)?

Macula of the saccule

List the auditory ossicles:

Malleus Incus Stapes

A lack of photoreceptors in this structure creates the "blind spot"

Optic disc

What is the margin between the photosenstive and nonphotosensitive regions of the retina called?

Ora serrata

What is the fat surrounding the eye called?

Orbital fat

Which structure converts vibrations in the endolymph into action potentials?

Organ of Corti

The [OUTER/INNER] segment of each photoreceptor is composed of hundreds of discs containing photopigments that are capable of absorbing light energy.

Outer

What's another name for the eyelids?

Palpebrae

What is the space behind the lens called?

Posterior cavity

RODS OR CONES: -They work well in dim light and there are more than 100 million of these cells in each eye

Rods

Perilymph is located in what 2 structures?

Scala tympani Bony labyrinth of the semicircular canals

Which structures are part of the vestibular complex?

Semicircular ducts Saccule Utricle

Which auditory ossicle contacts the oval window?

Stapes

What ligament connects the ciliary body to the lens?

Suspensory ligaments

List two muscles in the inner ear?

Tensor tympani Stapedius

Dark adaptation

The process in which the eyes become more sensitive to light in low illumination.

What is the roof of the cochlear duct formed by?

The vestibular membrane

The vitreous body is also called what?

Vitreous humor

The axons of the ganglion neurons of the retina terminate in the...

thalamus

Place the structures of the eye in order from superficial to deep. -Choroid -Photoreceptors -Bipolar cells -Horizontal cells

1. Choroid 2. Photoreceptors 3. Horizontal cells 4. Bipolar cells

Place the layers of the eye in order from superficial to deep: Vascular tunic Retina Fibrous tunic

1. Fibrous tunic 2. Vascular tunic 3. Retina

What structure is filled with pigment from melanocytes?

Choroid

What type of lens is used to treat myopia?

Concave

The junction of the palpebral and ocular conjunctiva is called what?

Conjunctival fornix

Upon exposure to light, the retina straightens out and reconfigures into a form called this:

Trans-retinal