Final answer:
Serum tubes with clot activator and gel are used to obtain serum, which is the plasma component of the blood without the coagulation factors.
Step-by-step explanation:
The question is about the process of collecting blood samples in serum tubes with a clot activator and gel. These tubes are used to obtain serum, which is the plasma component of the blood without the coagulation factors. Serum tubes with clot activator and gel are commonly used in medical laboratories to separate the serum from the blood cells allowing for further analysis and testing.