How many white blood cells are typically found in 1 mL of blood?

The typical range for white blood cells (WBCs) in 1 mL of blood is about 4,000 to 11,000 cells, which translates to approximately 4 to 11 million white blood cells per liter. Given that there are 1,000 mL in a liter, this converts to a range of 4 to 11 cells per mL, but when considering the options provided, 5 million is the closest and most representative estimate of the average number of white blood cells found in 1 mL of blood. This range is crucial for maintaining the immune response, and variations can indicate health issues or immune activity.