Final answer:
During the hour in the glass tube, the blood collected clots which separates the serum from the cellular components, allowing the lab technician to harvest the serum for further analysis.
Step-by-step explanation:
When a lab technician collects a blood sample in a glass tube, the following process happens over the course of an hour. Initially, the blood is in a liquid state containing both cells and plasma. As time passes, the blood clots due to the activation of coagulation factors present in the plasma. This results in the formation of a clot. The cellular components of the blood get trapped in the fibrin mesh of the clot, while the liquid part of the blood, now called serum, remains unclotted and is separated from the clot. The clotted blood separates from the serum, which is then harvested by the technician for further blood analysis. The process of serum separation is crucial for various diagnostic tests that require serum, which is free from cells and clotting factors.