Embryology

Question 1

The nerve fibers that emerge from the rental ganglion cells at ____ weeks travel along the ______ wall of the _________ to reach the brain

Answer 1

6th week
Inner wall
Optic stalk

Question 2

The lumen of the optic stalk is obliterated by growth of nerve fibers, by week ______, we have a __________

Answer 2

8

Solid optic nerve

Question 3

What are the 2 sources of vascularization

Answer 3

Choroidal layer

Hyaloid artery

Question 4

The hyaloid artery is a _______ artery

Answer 4

Transient

Question 5

What does the hyaloid artery develop from

Answer 5

A branch of the ophthalmic artery

Question 6

What does the hyaloid artery supply

Answer 6

The developing retina and lens vesicle

Question 7

What is the name given to the branches of the hyaloid artery that extend over the lens

Answer 7

Tunica vasculosa lentis

Question 8

The lips of the optic fissue fuse by day______ and enclose this

Answer 8

37

Enclose the hyaloid artery

Question 9

The hyaloid vascualture is maximally developed by what week gestation

Answer 9

10

Question 10

When the lens matures during fetal life and doesn’t need blood supply the hyaloid artery will degenerate. How does this occur

Answer 10

Macrophages will eat it

Question 11

What is the space formed by where the hyaloid artery was

Answer 11

Cloquets canal

Question 12

The proximal portion of the hyaloid artery becomes what?

Answer 12

The central retinal artery

Question 13

What does the central retinal artery supply

Answer 13

The retina

Question 14

Vascularization of the retina starts as the hyaloid artery is regressing and is predominant during the final trimester

Answer 14

Know this

Question 15

In week 6-7 the mesenchyme capsule of the optic cup forms these 2 layers

Answer 15

Inner pigmented layer, choroid

Outer fibrous, sclera

Question 16

The choroid layer is homologous in origin with what 2 things

Answer 16

Pia mater

Arachnoid membranes

Question 17

The sclera is ho Olomouc with his

Answer 17

Dura mater

Question 18

What does the choroid develop from

Answer 18

Neural crest cell-derived mesenchyme and mesoderm

Question 19

What does the sclera develop from

Answer 19

Mesenchyme tissue that is continuous with the cornea

Question 20

The cornea has 3 origins. What are they?

Answer 20

Head mesoderm: endothelium

Neural crest cells: stroma

Surface ectoderm: outer corneal epithelium

Question 21

Mesenchyme the overlays the lens splits into 2 layers and encloses this new cavity

Answer 21

Anterior chamber

Question 22

The anterior wall off the anterior chamber is continuous with this

Answer 22

Sclera

Question 23

The posterior wall of the anterior chamber is continuous with this

Answer 23

Choroid

Question 24

The pupillary membrane will regress early in fetal period (6-8 mo) and form this

Answer 24

Pupil

Question 25

The pupil allows communication between these 2 things

Answer 25

Anterior and posterior chamber

Question 26

What happens when the pupillary membrane fails to brain down

Answer 26

There are strands that traverse the pupil

Question 27

The Irish stroma develops from this

Answer 27

Mesenchyme of both neural crest and mesodermal origin

Question 28

The posterior iris epithelium and the smooth muscle bundles develop from this

Answer 28

Neuroepithelium of the optic cup

Question 29

The optic cup differentiates an folds to make

Answer 29

Ciliary body

Question 30

The mesenchyme cells that invade the choroid of the ciliary body form this

Answer 30

Smooth muscle bundles of the ciliary muscles

Question 31

In week 6, small folds of surface ectoderm develop above and below cornea They will grow and meet and fuse in this week

Answer 31

8th

Question 32

What is the space between the fused eyelids of the cornea called

Answer 32

Conjunctival sac

Question 33

The eye lids separate in this month

Answer 33

5-7th

Question 34

The eyelid muscles are derived from this

Answer 34

Mesoderm

Question 35

The lacrimal glands form from this

Answer 35

Invaginations of the surface ectoderm

Question 36

The lacrimal glands do not mature until ______

Answer 36

6 weeks after birth

Question 37

Look at the clinical correlates at the end of the lecture

Answer 37

Slide 17-19