Practice Questions

TLS Online TPP Program

#Question id: 5130

Regulation by gradients of paracrine factor concentration was elegantly demonstrated by the specification of different mesodermal cell types in the frog Xenopus laevis by activin, a paracrine factor of the TGF-beta family. Which of the following observations are correct from this graph?

#Unit 5. Developmental Biology

High concentrations of activin activate goosecoid, whereas lower concentrations activate Xbra.
Lower concentrations of activin activates only goosecoid not Xbra.
This pattern not correlates with the number of activin receptors occupied on individual cells.
In presence of activin neither the goosecoid nor the Xbra are activated