Holy

Question 0

Totipotent

Answer 0

Can give rise to all embryonic and extra-Embryonic cell types and structures

Question 1

Two essential features of stem cells:

Answer 1

• not terminally differentiated

- can self-Renew by dividing and producing 2 daughter cells (one differentiated and one stem cell)

Question 2

Pluripotent

Answer 2

Can give rise to all embryonic cell types and structures

Question 3

Multi potent

Answer 3

Can give rise to multiple (not all) cell types

Question 4

Unipotent

Answer 4

Can give rise to just one type of cell

Question 5

Dorsal-Ventral Axis

Answer 5

SHH secreted from ventral and BMP4 secreted from dorsal roof plate

Question 6

Left-right Axis

Answer 6

Lefty inhibits nodal on the right side and nodal inhibits lefty on the left side

Question 7

Anterior-PosteriorAxis

Answer 7

Hox genes- homeobox genes
RA (retanoic acid) involved in regulating Hox- exogenous RA can disrupt Hox gene expression

RA found in primitive node- helps develop posterior fate

Question 8

Big Five signaling Pathways involved in Development:

Answer 8

1. TGF pathway (transforming growth factor; includes TGF-beta, BMP, Activin and Nodal proteins)- neuronal differentiation
2. Hedgehog pathway (sonic hedgehog is protein mammals express)- neuronal differentiation
3. FGF pathway (fibroblast growth factor; includes a number of FGFs)-involved in eye formation
4. Wnt pathway
5. Notch pathway

Question 9

Epiblast

Answer 9

Part of the bilaminar disc, gives rise to the embryo proper and extraembryonic structures - tall layer of columnar cells closest to the amniotic cavity

Question 10

Hypoblast

Answer 10

Gives rise to extraembryonic structures - the underlying cells beneath the epiblast that are more cuboidal

Question 11

Gastrulation

Answer 11

The method by which germ layers are formed from the epiblast. It is the migration of epiblast cells toward the midline of the embryonic disc. The thickening formed by this = primitive streak.

Question 12

Primitive streak

Answer 12

serves to demarcate the anterior-posterior and left-right axis of the embryo.

Question 13

Hensen’s Node/Primitive Node

Answer 13

As epiblast cells continue migrating, the primitive streak extends along the disc and thickens and this node appears at the rostral end of the streak

Question 14

Trophoblast

Answer 14

Later forms the placenta, surrounds group of cells and amnion and blood is infiltrated into the trophoblast layers