Development B7 Flashcards
As the optic cup folds in upon itself, the “back” of the cup comes into contact with the layer from the front of the cup. They come together to form this “_____________________” relationship.
apex to apex
The small space left over by this process is initially called the ________________
Intraretinal space
Inner and outer layers of retina
Posteriorly: -Outer layer: RPE -Inner layer: Neural Retina More Anteriorly: -Outer layer: pigmented ciliary epithelium -Inner layer: Non-pigmented epithelium Most anterior: Outer layer: anterior iris epithelium Inner layer: posterior iris epithelium
When is the earliest pigmetation evident in the embryo?
week 3 to 4
After week __ the RPE is one cell thick.
6
At approximately week __, a inner and outer neuroblastic layer is forming. Between these 2 is the transient fiber layer of chievitz
7
Neural retina will subdivide into two distinct areas beginning around weeks ______
4 to 6
________ cells migrate, forming a layer close to the basement membrane which becomes evident by week 8.
Ganglion
_________ cells, located rather centrally in the inner neuroblastic layer, develop at the same time as ganglion cells.
Muller
The bodies of the Muller and amacrine cells remain in the inner neuroblastic layer but move slightly ______.
sclerad
By week 12 the ____________ are aligned along the outer side of the inner layer of the optic cup and.
photoreceptors
Which photoreceptors develop first?
Cones develop first then rods second
Adhering junctions form the precursor of the ___________________.
External limiting membrane
The photoreceptor cells are the last cells of _________ to differentiate, occurs during the 5th month.
neural retina
Where do Horizontal, Bipolar, Amacrine, and Muller cells develop at?
inner nuclear layer
inner and outer plexiform layers are filing with neuronal processes
The fibers of the Muller cells appear and extend to the basal lamina, forming the primitive ___________________.
internal limiting membrane
____________ cells provide a scaffolding for cell development and appears to be involved with guiding the direction of axonal fiber growth.
Muller
What do plexiform layers consist of?
Synapses of axon
WHat develop earlier? Rod spherules or cone pedicles?
Cone pedicles develop earlier
What came before what?
Central or peripheral?
Cones or rods?
Inner or outer?
Central before peripheral
COnes before rods
Inner plexiform layer before outer layer
(Photoreceptor synapses with bipolar cells are eztablished before the outer segments are completed)
By month 5 the ____________ layer is well established.
ganglion
Since retinal development happens before peripheral, what is significant here?
By the time peripheral nerves got their axons in place they have to detour up and around the central, this line of deviation is termed the HORIZONTAL RAPHE
By month 6 there is no further mitosis, and retinal growth continues because of cell _________, ________,and __________.
differentiation
growth
maturation
Foveal depression continues to deepen until about age 15 months as cells continue to move toward the _______________.
macular periphery
At birth there is still a single layer of ________ cells and a thin ________ layer across the now-depressed foveal area.
ganglion
inner nuclear
