What Is a Juxtamedullary Nephron? What Is a Juxtamedullary Nephron? What Is a Juxtamedullary Nephron? What Is a Juxtamedullary Nephron? What Is a Juxtamedullary Nephron? What Is a Juxtamedullary Nephron? What Is a Juxtamedullary Nephron? What Is a Juxtamedullary Nephron?