Vertebrate eye development

Question 1

What is expressed in the early eye field?

Answer 1

Rx, Six3 and Pax6

Question 2

What splits the eye field into 2?

Answer 2

Floor plate- expressing Shh

Question 3

What is holoprosencephaly?

Answer 3

A failure of the ventral forebrain to form- mutations in Shh/Shh signalling components

Question 4

Each eye field grows sideways and forms what?

Answer 4

Optic vesicle

Question 5

What does the eye field touch when it grows sideways and what does this cause?

Answer 5

The eye field touches the ectoderm- causing it to thicken and form the lens placode

Question 6

What does the placode form?

Answer 6

The lens

Question 7

What signalling occurs between the placode and optic vesicle?

Answer 7

Placode signals to optic vesicle causing a morphological transformation (forms a double layered cup structure)-> optic vesicle signals back to placode to induce it to become the lens

Question 8

What do lens fibre cells produce?

Answer 8

Crystallin- transparent protein

Question 9

What comes from the inner neural epithelium?

Answer 9

Stem-cell like population, ganglion cells, bipolar cells, amacrine cells, photoreceptors and muller glia

Question 10

What comes from the outer retinal pigment epithelium?

Answer 10

Pigmented cells- produce melanin

Question 11

Where do the cell bodies of the radial glia lie?

Answer 11

The ventricular zone

Question 12

Neuroblasts in the outer neuroblastic layer form?

Answer 12

Rods and cones

Question 13

Neuroblasts in the inner neuroblastic layer form?

Answer 13

Bipolar neurons

Question 14

Neuroblasts in the innermost neuroblastic layer form?

Answer 14

Ganglion cells

Question 15

Which genes promote retinal neuron cells to become bipolar cells?

Answer 15

CHX10

Question 16

Which genes promote retinal neuron cells to become horizontal cells?

Answer 16

PROX1