Embryogenesis

Question 1

What is the process in which the blastula rearranges into 3 germ layers? What are the 3 germ layers?

Answer 1

Process: gastrulation

3 layers: ectoderm, mesoderm, endoderm

Question 2

What two cell types does the inner cell mass give rise to?

Answer 2

Epiblast and hypoblast

Question 3

What molecular signals drive neurulation?

Answer 3

The dorsal lip of the blastopore is called Spemann’s organizer, and releases neural inducers such as the proteins Noggin and Chordin.

Question 4

What is neurulation?

Answer 4

Neurulation is the process in which the neural plate bends up and later fuses to form a hollow tube will eventually differentiate into the brain and spinal cord.

Question 5

‘Animal cap’ (dorsal ectoderm) derived from the blastula gives rise to?

Answer 5

Epidermis

If the ‘Animal Cap’ was derived the gastrula then it would give rise to neural tissue.

Question 6

What allows grafted blastopore cells to induce neural tissue in a region of ectoderm that would normally not give rise to the nervous system?

Answer 6

Spemann’s organizer

Question 7

What is the ‘Default Model’?

Answer 7

Neurogenesis is the default option for ectodermal maturation.
If ectoderm is cultured alone, all cells differentiate into neurons

Question 8

Chordin, Noggin and Follistatin all block the anitneuralizing effect of what signaling molecule?

Answer 8

BMP4