Histo

Question 1

what are the glands of our eyelids?

Answer 1

1. Tarsal (meibomian) glands -> secretion stops tears from evaporating. Blocking causes chalazion
2. Sebaceous gland of eyelashes -> infection causes a style
3. Lacrimal gland- makes our ears
4. Palpebral and bulbar conjunctiva -> thin mucus membrane (stratified columnar epithelium + goblet cells) that line inner eyelid and end lateral to cornea

Question 2

three basic layers of eye

Answer 2

1. Corneoscleral- outer layer that is penetrated by optic nerve. Made up of scar and cornea
2. Vascular coat (uvea) -> middle coat is made up of the choroid, stroma of ciliary. body, stroma of iris
3. Retina (inner coat that rests on choroid)

Question 3

what makes up retina

Answer 3

epithelium of ciliary body and iris

neural retina (photoreceptors and support cells)

retinal pigmented epithelium (RPE), absorbs light, prevents refections, component of blood-retinal barrier and phagocytoses

Question 4

vitreous chamber

Answer 4

space in between posterior surface of lens and the neural retina.

filed with vitreous humor to help maintain shape (99% water)

Question 5

corneoscleral coat is what?

Answer 5

made up of sclera (thick layer pierced by BV. NCs and optic nerve posteriorly)

cornea

Question 6

Cornea is the chief refractive element of the eye that is cont with the sclera. it has 5 layers . what are they

Answer 6

1. corneal epithelium:
2 Bowmans membrane
3. Corneal stroma
4. Descemet's membrane
5. corneal endothelium

Question 7

what is corneal epithelium

Answer 7

nonketatined. stratified squamous epithelium with stem cells

Question 8

2 Bowmans membrane

Answer 8

anterior basement membrane for epithelium

Question 9

3. Corneal stroma

Answer 9

a vascular layer of cells and stroma

Question 10

4. Descemet’s membrane

Answer 10

posterior basement membrane for the corneal endothelium

Question 11

5. corneal endothelium

cell type

Answer 11

simple squamous:

faces anterior chamber

Question 12

what is this image

Answer 12

corneoscleral junction

Question 13

what originates at the corneoscleral junction

Answer 13

smooth muscle

Question 14

What do ciliary processes secrete?

Answer 14

aqueous humor

Question 15

path. of humor

Answer 15

aqueous humor is secreted into posterior. chamber by. ciliary rocesses

fluid goes through. pupil -> anterior chamber (will give nutrients and O2 to avascular structures and maintain shape)

fluid taken up by limbus apparatus (canal of schlemm)

Question 16

3. components of lens

Answer 16

1. capsule- flexible elastic ECM
2. Subcapsular lens epithelium- cells on periphery migrate to make mature lens fiber cells. this decreases w age
3. lens fibers- filled with crystallins and lose all orgnalles: central lens nucleus laid down during embryo development

Question 17

what is the RPE

Answer 17

retina pigmented layer (RPE) is a layer of simple cuboidal epithelial cells that res on Bruch’s membrane of the choroid.

Question 18

Actions of RPE

Answer 18

1. serves as blood-neural rettinal layer and absorbs stray light
2. Phagocytoses membranous discs shed from rods and cons
3. isomerize all-trans retinal to 11-cis retinal, transporting back to photoreceptors

Question 19

what are the the layers of the retina

Answer 19

1. RPE—not part of the neural retina
2. Rod and cone ends of photoreceptor cells
3. Outer limiting membrane—apical boundary of
   Müller cells (row of zona adherens attaching
   apical ends of Müller cells)
4. Outer nuclear layer—cell bodies (nuclei) of
   photoreceptor cells
5. Outer plexiform layer—processes of
   rods/cones & processes of horizontal, amacrine
   & bipolar cells connecting them
6. Inner nuclear layer—cell bodies (nuclei) of
   horizontal, amacrine, and bipolar cells
7. Inner plexiform layer– processes of
   interconnecting ganglion, amacrine, bipolar,
   and horizontal cells
8. Ganglion layer—cell bodies (nuclei) of ganglion
   cells
9. Layer of optic nerve fibers—processes of
   ganglion cells
10. Inner limiting membrane—basement
    membrane of Müller cells

Question 20

what is the first layer light. hits in the retina?

Answer 20

inner limiting membrane - the BM. of muller cells

Question 21

what visual pigments do rods and cones have

Answer 21

rhodopsin

cones have iodopsin

Question 22

where are there no photoreceptors present

Answer 22

optic disk (optic nerve region

Question 23

Retinoblastoma

Answer 23

autDOM disorder mutation in Rb gene on chromo 13q14.1, which suppressors tumors.

develops in kids younger than 5 yo and causes a leukocorioa (white reflection off eyes and strabismus

Question 24

fovea centralis

Answer 24

highest concentration of cones and is AVASCULAR; surrounded by. macula lute

Question 25

Describe how the lens changes shape including the functions of the ciliary muscles and ciliary zonular
fibers.

Answer 25

we undergo accommodation by. tension from ciliary. body transited via zonular fibers -> lens, changing its shape

Question 26

what makes up organ cort

Answer 26

1. sensory. hair cells
2. inner and outer phalangeal cells (support for hair cells)
3. Pilar cells (support between BM and tympanic lip

Question 27

Basilar membrane vibrates with sound causing
deflection of ____ attached to tectorial
membrane—initiates neural transduction carried by
cochlear nerve

Answer 27

sterocilia

Question 28

_____ contains saccule and utricle , each which have a macula.

Answer 28

vestibule

Question 29

what is at the macula

Answer 29

cluster of hair cells with
stereocilia covered in otolithic membrane.

Otolithic membrane covered with Ca2+/carbonate protein called otoconia.

Question 30

action of utricle and saccule

Answer 30

gravity and acceleration

Question 31

Threes in the Audio-Vestibular System EXCEPT

Answer 31

BUT, only two maculae, capable of detecting linear acceleration in three
dimensions

Question 32

Three nerves in the internal acoustic meatus

Answer 32

Vestibular nerve
– Acoustic nerve
– Facial nerve