In the context of rtk signaling, ras is active when bound to:
a. mapk
b. gdp
c. gtp
d. sos

GTP.

Explanation:

Ras MAP kinase is an important cell signalling process that are important for cell survival, cell multiplication and cell proliferation. The phosphorylation at particular reside play important role in this signalling.

The binding of GDP with Ras indicates that Ras pathway is inactive. The exchange of GDP with GTP activates the Ras pathway and initiates the signalling cascades that further activates the MEK signalling. Hence, Ras is active when bound to GTP.

Thus, the correct answer is option (c).

equal distribution i think.