Canadian Society for Medical Laboratory Science (CSMLS) Practice Exam

In a clinical laboratory, what is a common application of a hemocytometer?

1. Measuring reagent concentrations

2. Counting blood cells

3. Assessing enzyme activity

4. Analyzing pH levels

The correct answer is: Counting blood cells

A hemocytometer is a specialized counting chamber that is primarily used for counting blood cells and other types of cells in a laboratory setting. Its design allows for precise enumeration of cells by placing a sample on a calibrated grid, enabling technicians to count cells accurately under a microscope. This is particularly important in clinical settings where accurate cell counts can influence diagnosis and treatment plans. In contrast, measuring reagent concentrations typically involves techniques such as spectrophotometry or titration, which do not utilize a hemocytometer. Assessing enzyme activity is generally evaluated using specific assays designed for that purpose, rather than through cell counting. Analyzing pH levels usually requires pH meters or indicators, which are not related to the functions of a hemocytometer. Thus, the common application of a hemocytometer is specifically and effectively for counting blood cells.