Eye Flashcards
1
Q
What makes up the fibrous layer of the eye?
A
- Cornea2. Sclera
2
Q
The cornea and sclera make up what layer of the eye?
A
Fibrous
3
Q
What makes up the vascular layer of the eye?
A
- Choroid2. Ciliary body3. Iris
4
Q
The choroid, ciliary body, and iris make up what layer of the eye?
A
Vascular
5
Q
What makes up the retinal layer of the eye?
A
- Neural layer2. Retinal pigment epithelium
6
Q
What are the contents of the posterior chamber?
A
- Aqueous humor2. Iris3. Ciliary body and muscle4. Lens5. Cornea6. Anterior sclera
7
Q
What are the contents of the vitreous chamber?
A
- Vitreous humor2. Visual retina3. Retinal pigment epithelium4. Posterior sclera5. Uvea
8
Q
What are the five layers of the cornea?
A
- Corneal epithelium (most external)2. Bowman’s membrane3. Corneal stroma4. Descemet’s membrane5. Corneal endothelium
9
Q
What type of cell makes up the corneal epithelium?
A
Stratified squamous non-keratinized with apical microvilli
10
Q
What protein protects the corneal epithelium from UV damage?
A
Ferritin
11
Q
What are some functions of Bowman’s membrane?
A
- Contributes to strength and stability of cornea2. Acts as barrier to prevent spread of infections
12
Q
What are some characteristics of the corneal stroma?
A
- 90% of cornea’s thickness2. Collagen fibrils arranged in lamellae (transparency)3. Proteoglycans and collagen V allow proper spacing of collagen fibrils
13
Q
What are some characteristics of Descemet’s membrane?
A
- Regenerates after injury2. Thickens with age3. Interwoven meshwork of fibers and pores4. Helps maintain curvature of cornea
14
Q
What are some characteristics of the corneal endothelium?
A
- Faces anterior chamber - has zonula occludens, adherens, and desmosomes2. Simple squamous epithelium3. Responsible for virtually all metabolic exchanges of cornea - nutrition via diffusion
15
Q
- Contributes to strength and stability of cornea2. Acts as barrier to prevent spread of infections
A
Bowman’s membrane
16
Q
- 90% of cornea’s thickness2. Collagen fibrils arranged in lamellae (transparency)3. Proteoglycans and collagen V allow proper spacing of collagen fibrils
A
Corneal stroma
17
Q
- Regenerates after injury2. Thickens with age3. Interwoven meshwork of fibers and pores4. Helps maintain curvature of cornea
A
Descemet’s membrane
18
Q
- Faces anterior chamber2. Simple squamous epithelium3. Responsible for virtually all metabolic exchanges of cornea
A
Corneal endothelium
19
Q
What is Tenon’s capsule?
A
Fascial sheath over the surface of the sclera where extraocular muscles insert
20
Q
Fascial sheath over the surface of the sclera where extraocular muscles insert
A
Tenon’s capsule
21
Q
What is the corneoscleral limbus?
A
- Location of stem cells for corneal epithelium2. Location of iridocorneal angle
22
Q
- Location of stem cells for corneal epithelium2. Location of iridocorneal angle
A
Corneoscleral limbus
23
Q
What is the iridocorneal angle?
A
- Trabecular meshwork2. Formation of Canal of Schlemm (scleral venous sinus)3. Apparatus for the outflow of aqueous humor
24
Q
- Trabecular meshwork2. Formation of Canal of Schlemm (scleral venous sinus)3. Apparatus for the outflow of aqueous humor
A
Iridocorneal angle
25
What is the ora serrata?
Area that defines anterior limit of retina and choroid and the posterior limit of the ciliary body
26
Area that defines anterior limit of retina and choroid and the posterior limit of the ciliary body
Ora serrata
27
What are the functions of the ciliary processes?
1. Secretion of anchoring zonule fibers2. Produce aqueous humor3. Blood-aqueous barrier
28
What is the flow of aqueous humor?
Posterior chamber --> pupil --> anterior chamber --> trabecular meshwork --> Canal of Schlemm --> venous system
29
What is the function of ciliary muscle?
Reduce tension on lens for near vision
30
What is Bruch's membrane (lamina vitrea)?
Thin, amorphous hyaline membrane that forms the innermost layer of the choroid
31
What is contained in the fovea centralis?
Only cone photoreceptor cells - area of highest visual acuity
32
What is the retinal pigment epithelium?
Attaches via Bruch's membrane to the choriocapillary layer of the choroid (site of dislocated retina)
33
What are the four groups of cells found in the retina?
1. Photoreceptors2. Conducting neurons3. Association and other neurons4. Supporting (neuroglial) cells
34
What is the function of the RPE?
1. Absorb light2. Blood-retina layer3. Metabolic processes4. Phagocytosis of membranous discs from rods and cone
35
Iodopsin is sensitive to what colors?
Red, green, blue
36
What is the main blood supply to the retina?
Central retinal artery from ophthalmic artery
37
What are the three parts of the lens?
1. Capsule2. Subcapsular epithelium3. Lens fibers
38
Conjunctiva is made up of what type of epithelium?
Stratified columnar with goblet cells and basal lamina overlying a loose CT
39
Can Bowman's membrane regenerate?
No
40
What is the precise location for stem cells of the corneal epithelium?
Corneoscleral limbus
41
What is the dilator pupillae's arrangement of fibers with respect to the iris?
Radially arranaged
42
What is the sphincter pupillae's arrangement of fibers with respect to the iris?
Circularly arranged
43
How is the dilator pupillae innervated?
Sympathetic nervous system
44
How is the sphincter pupillae innervated?
Parasympathetic nervous system
45
What imparts pigment to the iris?
Anterior and posterior pigment epithelium
46
What causes open angle glaucoma?
Blockage of trabecular meshwork, slowing drainage of aqueous humor
47
What causes closed angle glaucoma?
Iridocorneal junction narrows / pinches off
48
Which is more emergent - open angle or closed angle glaucoma?
Closed
49
What is the pathogenesis of diabetic retinopathy?
Fragility of blood vessels - leads to retinal bleeding, edema, neovascularization of retina and iris
50
What is a common early sign of age related macular degeneration?
Drusen
