The metanephrogenic blastema or metanephric blastema (or metanephric mesenchyme, or metanephric mesoderm) is one of the two embryological structures that give rise to the kidney (the other is the ureteric bud.)The metanephric blastema mostly develops into nephrons, but can also form parts of the collecting duct system.The system of tissue induction between the ureteric bud and the metanephric blastema is a reciprocal control system.