What is the purpose of a blood smear?

A blood smear is a laboratory technique used primarily to evaluate blood cell morphology, which involves the examination of the shape, size, and structure of blood cells. In this process, a thin layer of blood is spread on a microscope slide and then stained to highlight the different cellular components. This allows for the identification of various blood cells, including red blood cells, white blood cells, and platelets. By assessing their morphology, medical professionals can diagnose a range of conditions, such as anemia, infections, and blood disorders.

The other options refer to different laboratory tests that focus on specific aspects of blood analysis. Analyzing clotting ability involves specialized tests such as prothrombin time or activated partial thromboplastin time, which assess the coagulation factors within the blood. Measuring blood glucose levels typically requires a blood sample tested using a glucometer or laboratory analysis that specifically targets glucose concentration. Determining blood type involves serological testing to identify the presence of A, B, AB, or O antigens on the surface of red blood cells, which is unrelated to morphology assessment. Thus, the primary purpose of a blood smear is to evaluate blood cell morphology.