Final answer:
Serum cannot coagulate because fibrinogen, a vital coagulation factor necessary for the blood clotting process, has been removed.b) Fibrinogen
Step-by-step explanation:
Serum can't coagulate because the fibrinogen has been removed. The correct answer is b) Fibrinogen. Serum is essentially blood plasma that is lacking in coagulation factors, which includes fibrinogen. Fibrinogen is a soluble protein that is converted to the insoluble protein fibrin during the coagulation process. Fibrin forms a mesh that helps to trap platelets and red blood cells to produce a clot. Without fibrinogen, this process cannot occur, thus serum remains unable to coagulate.
Plasma and serum are both components of blood that have distinct differences. While plasma contains all the components of blood including the coagulation factors and antibodies, serum is the component of plasma without coagulation factors. This difference is critical when it comes to the ability of blood to form clots and is why serum cannot participate in coagulation.