Final answer:
The metanephric blastema differentiates into the nephrons of the kidney.
Step-by-step explanation:
The metanephric blastema, also known as the metanephric mesenchyme, differentiates into the structures of the kidney known as the nephrons. The nephrons are the functional units of the kidney responsible for filtering blood and forming urine. They consist of the renal corpuscle, which includes the glomerulus and Bowman's capsule, and the renal tubules.