Which component is typically considered the heaviest of all formed elements in blood?

The option that indicates red blood cells as the heaviest of all formed elements in blood is correct because red blood cells, or erythrocytes, are more numerous and have a greater volume compared to the other components. They account for the majority of the formed elements in blood, which includes white blood cells (leukocytes) and platelets (thrombocytes), as well as the liquid component of blood, which is plasma.

Red blood cells are responsible for oxygen transport and are filled with hemoglobin, which contributes to their density and weight. This is why they settle at the bottom when blood is spun in a centrifuge, separating the different components based on their density. In clinical settings, understanding the order of formed elements is crucial for accurate blood analysis and diagnostics.

White blood cells and platelets are present in much lower quantities than red blood cells, which is why they do not have the same mass or weight in the blood. Serum is the liquid component that remains after blood has clotted and the cells have been removed, so it does not have weight in terms of formed elements.