. "\"Any process that initiates the activity of an inactive GTPase of the Ras superfamily through the replacement of GDP by GTP.\" [GOC:dph, GOC:mah, GOC:tb]" . . "activation of Ras GTPase activity" . "Ras GTPase activation" . "Note that this term should not be confused with the molecular function term 'Ras GTPase activator activity ; GO:0005099', which refers specifically to the activity of Ras GAPs." . .