Blood serum

Serum is a yellow fluid that remains after the coagulation of a blood sample, followed by a removal of the blood clot from the sample. It does not contain any cellular elements and clotting factors (such as fibrinogen), which distinguishes it from blood plasma. Both plasma and blood serum contain electrolytes, antibodies, hormones and other proteins that do not contribute to blood clotting.

Related articles

 * Blood
 * Plasma
 * Plasma vs. Serum