Friday, 4-8-Histology of visual, vestibular, and auditory systems (Olinger)

Question 1

List the components of the outer tunic:

Answer 1

sclera and cornea

Question 2

list the components of the middle tunic

Answer 2

uvea, choroid, iris, and ciliary body

Question 3

list the components of the inner tunic:

Answer 3

retina

Question 4

Regarding the outer tunic, the __ is transparent and the rest of the wall of the eye is opaque and lined by the middle of vascular pigmented layers that absorb light which is known as the __

Answer 4

cornea

sclera

Question 5

the basal cells of the corneal epithelium are anchored to Bowman’s layer by ___.

Myelinated nerves can be found in the __ of the cornea.

After crossing __ layer, nerves become unmyelinated and extend toward the surface in the intercellular spaces of the corneal epithelium

___ part of the cornea is permeable to air oxygen used for various oxidative rxns, in particular glutathione reduction and oxidation

Answer 5

hemidesmosomes

stroma

Bowman’s

corneal endothelium

Question 6

In the posterior 2/3 of the eye, the vascular layer is called the ___. In the anterior part of the eye the vascular layer thickens to form the ___ and have ciliary processes that extend inward from it.

The smooth muscle of the ciliary body regulates the tension of the zonule or suspensory ligament of the lens and, therefore, is an important element in the mechanism of __

Answer 6

choroid

ciliary body

accomodation

Question 7

contraction of the __ relaxes the tension exerted by the zonular fibers on the lens during accomodation

Answer 7

ciliary muscles

Question 8

What separates the anterior chamber from the posterior chamber?

Answer 8

the iris –> anterior surface lacks epithelial lining, posterior surface is lined by a dual layer of pigmented epithelial cells, a direct continuation of the pigmented layer of the retina.

Question 9

___ consists of myoepithelial cells, contains alpha-adrenergic receptors and is innervated by sympathetic nerve fibers.

Answer 9

dilator pupillae-contraction causes pupil dilation or mydriasis

Question 10

___ consists of smooth muscle cells, has Ach receptors and innervated by parasympathetic nerve fibers.

Answer 10

sphincter pupillae-contraction reduces the diameter of the pupil (miosis)

Question 11

Aqueous humor is secreted by the __

Answer 11

epithelial cells of the cilliary processes

Question 12

List the cell types for the following retinal neurons:

Photoreceptor neurons: ___

Conducting neurons: ___

Association neurons: ___

Supporting neuroglial cells: ___

Answer 12

rods and cones

bipolar and ganglion cells

horizontal and amacrine cells

Muller cell

Question 13

This is the only photoreceptor present in the fovea: ___

Answer 13

cones-where fine detail is present

Question 14

Where are the nuclei of rods and cones present?

The axons of the rods and cones project into the __ layer and synapse with dendrites of the __ cells

Answer 14

in the outer nuclear layer

outer plexiform

bipolar

Question 15

Nuclei of the bipolar cells contribute to the __ layer

Axons of the bipolar cells synapse with dendrites of the ganglion cells in the __ layer

Axons of the ganglion cells become part of the ___

Answer 15

inner nuclear

inner plexiform

optic n.

Question 16

The __ corresponds to junctional complexes (zonula adherens) between rods, cones, and Muller cells

__ cells synapse with several rods and cones

__ cells synapse with axons of bipolar cells and dendrites of ganglion cells

Answer 16

outer limiting membrane

horizontal

amacrine

Question 17

At the __, tightly packed cones are arranged at an angle to the pigmented layer.

Answer 17

fovea centralis

Question 18

The axons of the ganglion cells turn into the optic n. at the ___, which lacks photoreeptors and corresponds to the blind spot of the retina

Answer 18

optic disk

Question 19

The __ is a yellow spot produced by xanthophyll pigments within retinal cells, which may absorb short wavelength light and provides for central vision. In its center, the __ is for high-quality vision

Answer 19

macula lutea

fovea

Question 20

Cones are concentrated in the ___ and are responsible for acute vision and color distinction.

Answer 20

macula

Question 21

Detachment of the retina is a separation of 2 layers of the retina. It can be caused by:

Answer 21

trauma, vascular disease, metabolic disorders, and aging

Question 22

The 2 genes for the red and green photopigment reside on the __ chromosome and contribute to red-green color blindness

Answer 22

X

Question 23

Trace the pathway of the flow of aqueous humor

Answer 23

From the ciliary body through the posterior chamber –> pupil –> anterior chamber –> trabecular meshwork –> canal of schlemm –> aqueous veins –> episcleral veins

Question 24

Blockage of aqueous humor where can lead to glaucoma?

Answer 24

at the canal of schlemm (most common)

inflammation preventing aq humor from reaching trabecular meshwork

Question 25

__ extend from the ciliary epitheium to the equatorial region of the capsule and hold the lens in place

Answer 25

zonular fibers

Question 26

When the ajor proteins of the lens become insoluble, opacity of the lens develops. This condition is known as:

Answer 26

cataracts

Question 27

__ secrete a lipid-containing product that retards evaporation of the tear film. Infections and disruption of these causes chalazion (swelling of eyelid)

Answer 27

Tarsal glands

Question 28

The __ is a stratified-to-columnar epithelium with mucus-secreting goblet cells, supported by a thin lamina propria. It lines the anterior surface of the eyeball up to the limbus and the inner surface of the eyelid

Answer 28

conjunctiva

Question 29

The 3 semicircular ducts (superior, posterior, horizontal) open into the ___

Each ampulla contains ___. Sensory receptors inside of this respond to the position of the head, generating nerve impulses necessary for correcting the position of the body

Answer 29

utricle

crista ampullaris

Question 30

ductules emerging from the utricle and saccule join to form the ___

Answer 30

endolymphatic duct

Question 31

the endolymphatic duct ends in a dilated endolymphatic sac located in the __

Answer 31

subdural space of the brain

Question 32

The ___ connects the saccule to the base of the membranous coiled cochlear duct or scala media

Answer 32

ductus reuniens

Question 33

the __ extends from the vestibular area (which contains the saccule and the utricle) to the subarachnoid space around the brain

The __ fluid has a composition similar to CSF surround the membranous labyrinth

Answer 33

perilymphatic duct

perilymph

Question 34

The __ are sensory receptor areas located in the wall of the saccule and utricle. They are concerned with the detection of directional movement of the head

Answer 34

maculae

Question 35

The position of the macula in the utricle is __.

The position of the macula in the saccule is ___.

Answer 35

horizontal

vertical

Question 36

Inward movement toward the kinocilium deforms the plasma membrane and triggers ___

Displacement of the stereocilia away from the kinocilium lifts the kinocilium and causes __

Answer 36

depolarization

hyperpolarization

Question 37

__ hair cells predominate at the ridge of the crista, where as ___ hair cells are more numerous at the base

Answer 37

Type I

Type II

Question 38

Which scala contains endolymph?

Which scale contains perilymph?

Answer 38

endolymph=scala media

perilymph=scala vestibule and tympani

Question 39

The __ at the apex or cupula of the cochlea links the perilymph-filled scala vestibule and scala tympani

Answer 39

helicotrema

Question 40

An inward movement of the stapes against the oval window-caused by airborne sound-is transmitted to the cochlead partition by the noncompressible ___

Answer 40

perilymph fluid

Question 41

The osseous ___ is a bony shelf projecting from the modiolus. It forms canals for the cochlear nerve fibers

Answer 41

spiral lamina

Question 42

The ___ is located in the scala media and extends the full length of the basilar membrane. Its sensory receptors are hair cells

Answer 42

organ of corti

Question 43

Which hair cells are in direct contact with the tectorial membrane?

Answer 43

outer hair cells

Question 44

This membrane separates endolymph from perilymph and moves up in response to perilymph movement in the scala tympani, causing taller stereocilia of the outer hair cells to hit the tectorial membrane

Answer 44

Basilar membrane