Embryogenesis and Physiology of the Eye

Question 1

3 germ layers formed during gastrulation

Answer 1

Ectoderm
Mesoderm
Endoderm

Question 2

Germ layers that form the eye

Answer 2

Ectoderm and Mesoderm

Question 3

These are transient migratory stem cells that form with ectodermal and mesodermal characteristics

Answer 3

Neural Crest cells

Question 4

Ectomesenchymal cell population arising from neural ectoderm at the dorsal edge of the neural tube

Answer 4

Neural crest cells

Question 5

The optic nerve is derived from which SPECIFIC embryonic tissue?

Answer 5

Neuroectoderm

Question 6

The melanocytes of the eye are derived from which SPECIFIC embryonic tissue?

Answer 6

Neural crest cells of the ectoderm

Question 7

The retina is derived from which SPECIFIC embryonic tissue?

Answer 7

Neuroectoderm

Question 8

The epithelium of the (skin, cornea, conjuctiva and caruncle) is derived from which SPECIFIC embryonic tissue?

Answer 8

Surface ectoderm

Question 9

The endothelium of all eye and orbital blood vessels are derived from which SPECIFIC embryonic tissue?

Answer 9

Mesoderm

Question 10

The lacrimal gland is derived from which SPECIFIC embryonic tissue?

Answer 10

Surface ectoderm

Question 11

The temporal portion of the sclera is derived from which SPECIFIC embryonic tissue?

Answer 11

Mesoderm

Question 12

The ciliary muscle is derived from which SPECIFIC embryonic tissue?

Answer 12

Neural crest cells

Question 13

The dilator and sphincter muscle of the iris are derived from which SPECIFIC embryonic tissue?

Answer 13

Neuroectoderm

Question 14

The trabecular meshwork is derived from which SPECIFIC embryonic tissue?

Answer 14

Neural crest cells

Question 15

The Corneal stroma and endothelium are derived from which SPECIFIC embryonic tissue?

Answer 15

Neural crest cells

Question 16

Which part of the cornea is responsible for the maintenance of the dehydrated state of the cornea to keep it transparent?

Answer 16

Corneal endothelium

Question 17

This structure appears on each side of the neural fold at DAY 22 of embryogenesis

Answer 17

optic primordium

Question 18

The inner lining of the optic vesicle is made up of:

Answer 18

neural ectoderm cells

Question 19

The formation of lens placode is a result of the contact between:

Answer 19

optic vesicle and surface epithelium (inner aspect)

Question 20

At what gestational age (day) does the optic vesicle invagination occurs?

Answer 20

Day 25 (or Day 29)

Question 21

At day 29, the embryonic fissure found at the end of each stalk allows entry of:

Answer 21

Mesenchymal cells
Hyalloid artery

Question 22

At what gestational age (day) does the embryonic fissue of the optic vesicle closes?

Answer 22

Day 33

Question 23

The failure of closure of the embryonic fissure results in:

Answer 23

COLOBOMA

Question 24

At what gestational age (day) does the lens vesicle formation occur?

Answer 24

Day 37

Question 25

In the 37th day of gestation, the hyaloid arteries are retained and pierces through the:

Answer 25

optic nerve

Question 26

Which of the nuclei of the lens is the first to change in color when cataract develops?

Answer 26

embryonic nuclei