L6 - Ventralisation of the neural tube

Question 1

What is a morphogen?

Answer 1

A morphogen is a secreted, diffusible molecule that is distributed in a conc gradient from a fixed source.

• They generate discrete cellular states in response to different thresholds of the conc gradient. These cell states are to do with differential gene expression.
• Morhphogens are instructive in a direct manner.

Question 2

is the notochord part of the neural tube?

Answer 2

NO the notochord is not part of the neural tube, the notochord is located UNDER the neural tube not in it.