Histology Of Eye And Ear - 4/8 Olinger Flashcards
What is the transition zone between the cornea and sclera called?
Limbus
Describe the layers of the cornea from outer to inner:
Thick corneal epithelium Bowman's layer Stroma Descernet's membrane Corneal epithelium
How is Bowman’s cells layer anchored to the corneal epithelium?
Hemidesmosomes
The ciliary processes are attached to the lens via what?
What is it important in?
Zonule fibers/suspensory ligament
Accommodation
Which layer of the iris is lacking epithelium?
Anterior surface
Where is the blind spot/area w/out photo receptor cells?
Papilla
Where is the highest visual acuity location?
Fovea centralis
What produces the macula Lutea?
Located where?
Xanthophyll pigments
Retinal cells
Detachment of the retina results in what functionally?
Caused by what?
Separation of 2 layers of retina
Trauma, vascular disease, metabolic disorders, aging
Where do bipolar cell axons synapse onto ganglion cell dendrites?
Inner plexiform layer
Where do photo receptor cell axons synapse onto bipolar cell dendrites?
Outer plexiform layer
The nuclei of rods and cones are located where?
Outer nuclear layer
Where are the nuclei of bipolar cells located?
Inner nuclear layer
What do horizontal cells synapse with?
Rods and cones
What do amacrine cells synapse with?
Axons of bipolar cells and dendrites of ganglion cells
What makes aqueous humor?
Epithelial lining of the ciliary process
Describe the pathway of aqueous humor:
Ciliary process -> posterior chamber -> anterior chamber -> trabecular meshwork -> Canal of Schlemm -> aqueous and episcleral veins
What causes Glaucoma?
Obstruction of aqueous humor that causes increased intraoccular pressure
Via blockage of meshwork or Schlemm
Describe the cells located in the anterior lens
Middle region
Equatorial region
Flattened cells
Elongated cells, heavy mitosis
Cortical lens fibers
Cataracts is what?
Caused by what?
Opacity of the lens caused by change in the solubility of lens proteins
Aging and diabetes
Function of tarsal glands?
Secrete a lipid-containing product that retards evaporation of the tear film
Describe the conjunctiva, and what is the fx?
Stratified-to columnar epithelium w/goblet cells, supported by a thin LP
Fx: moisten eyeball
What is the tensor tympani muscle attached to?
Malleus
The peri lymphatic duct extends from where to where?
Dumps what?
Vestibular area (saccule and utricle)
Subarachnoid space
Perilymph fluid into CSF
The endolymph communicates how?
Located where?
With the endolymphatic duct to the endolymphatic sac
Subdural space
The cilia most responsible for depolarization of hyperpolarization of the utricle and saccule is what?
IN or OUTward movement for depolarization?
Kinocilium
Inward movement for depolarization (towards kinocilium)
All the canals communicated where?
Utricle
In the ampulla of the semicircular canal, Type 1 hair cells are located where?
Type 2?
Ridge of the crista
Base of cupula
How does sound enter the cochlea?
Exit?
Oval window
Round window
What makes up the cochlear duct?
Scala vestibuli, media, tympani
What separates Scala vestibuli from Scala media?
Reissner’s/vestibular membrane
What separates Scala media from Scala tympani?
Organ of corti
What is located in the Scala media?
Stria vascularis
What kind of fluid is located in Scala media?
What kind of ion content?
Endolymph
High K+
Where is perilymph located?
Scala vestibuli
Scala tympani
What is in direct contact with the tectorial membrane?
Outer hair cells
Where do vibrations start?
This is connected to what?
Describe the rest of the hearing pathway
Scala vestibuli connected to oval window
Then to helicotrema -> Scala tympani -> round window
What are the layers of the tunics? What is contained in them?
Outer - sclera and cornea
Middle(uvea) - ciliary process, choroid, iris
Inner - retina
