Lesson 11

Question 1

Eyes develop from three sources:

Answer 1

the neuroectoderm of the forebrain
(retina, iris and optic nerve)

the surface ectoderm of the head
(lens)

the head mesenchyme of neural
crest origin between these layers
(vascular and fibrous coats)

Question 2

Formation of the eye begins in the
medially near the anterior margin of
the future _______.

Answer 2

future prosencephalon

Question 3

Interactions of this area with the
underlying ______ will eventually
lead to lateral ___-___ regions.

Answer 3

mesoderm and lateral eye-forming regions

Question 4

Shallow grooves are formed
on the sides of the forebrain at what week of gestation? (Optic up and lens vesicle formation)

Answer 4

third week of gestation

Question 5

At the third week of gestation in most
species, shallow grooves are formed
on the sides of the forebrain.
These grooves will then expand as
the ___ ___

Answer 5

optic vesicles

Question 6

It has been shown in the mouse that
this is expressed very early in the optic field, iin its absence, the optic vesicles fail
to form.

Answer 6

the transcription factor Rx

Question 7

T OR F?
Each optic vesicle grows laterally until
it comes into contact with the surface
ectoderm

Answer 7

T

Question 8

In optic cup and lens vesicle formation: Each optic vesicle grows laterally and comes contact with the surface ectoderm which will induce the latter to create ?

Answer 8

Lens placode

Question 9

Lens placode invaginate and becomes?

Answer 9

Lens vesicles

Question 10

Lens vesicle develop and invaginate into?

Answer 10

optic cups

Question 11

Inner layer of optic ups becomes what structure afterwards? (hint: its for visual perception)

Answer 11

neural retina

Question 12

Then , the outer layer of optic cup turns into?

Answer 12

pigmented layer of retina

Question 13

The outer lips of optic cups gives rise to these two structures called?

Answer 13

Iris & ciliary body

Question 14

In what species, is the retinal differentiation and maturation completed at birth?

Answer 14

ungulates

Question 15

Retinal differentiation
and maturation continue for up to 5
weeks after birth on this species.

Answer 15

carnivores

Question 16

The last retinal cells to differentiate are
the ___ ___ and the receptor cells called __ & __ cells.

Answer 16

bipolar neurons
receptor cells
– the rod and cone cells.

Question 17

In optic axon, it connects the retina with
the diencephalon

Answer 17

optic stalk

Question 18

In what part of the surface of the stalk has a
groove, called the choroid fissure, that
contains the hyaloid vessels.

Answer 18

ventral surface

Question 19

Later, the ___ ___ closes and a
tunnel is formed inside the optic stalk.

Answer 19

choroid fissure

Question 20

A number of n___ f____ in the inner
wall of the stalk increases.

Answer 20

nerve fibers

Question 21

Eventually the inside and outside walls
of the stalk fuse, transforming the optic stalk into ___ ____?

Answer 21

optic nerve

Question 22

In optic axon, The optic nerve carries the what part of the retina?

Answer 22

central artery of the retina.