What is the normal percentage of solids in a sample of human blood?

Blood is composed of both liquid and solid components. The liquid part, known as plasma, constitutes about 55% of the total blood volume, while the solid components consist of cells and other substances, which together account for approximately 45% of the total volume. This solid portion is primarily made up of red blood cells, white blood cells, and platelets.

The figure of 45% aligns with the hematocrit, which is a common measurement used to assess the proportion of blood volume that is made up of cells. A normal hematocrit value for adults typically ranges from 38% to 52% for women and 40% to 54% for men, closely reinforcing the idea that around 45% of blood is solids. Therefore, the chosen answer accurately reflects the normal percentage of solids in a sample of human blood.