Here's why:
* Blood is composed of:
* Plasma: The liquid portion of blood, containing water, proteins, electrolytes, and other substances.
* Cells: Red blood cells, white blood cells, and platelets.
* When a clot forms: The platelets and clotting factors in the plasma work together to form a mesh of fibrin. This traps red blood cells, forming the visible clot.
* The remaining liquid: The liquid left behind after the clot forms is called serum. It's essentially plasma without the clotting factors.
Important Note: It's important to note that the clear liquid seen after a clot forms is not always serum. If it's reddish in color, it indicates the presence of red blood cells and is called plasma.
