Serum and plasma are two essential liquid components of blood, often used interchangeably, but they’re not the same. Understanding the serum vs plasma difference is vital for healthcare, diagnostics, and research. In this guide, we'll explain: What is serum in blood

Human blood types vary across eight common ABO/Rh groups, but a few are exceptionally rare and clinically critical. The rarest blood type is Rh null, often called “golden blood,” followed by subtypes like Bombay (HH) and AB–. This guide explores: What