How are the five types of leukocytes primarily distinguished?

The five types of leukocytes, or white blood cells, are primarily distinguished based on their size, the appearance of the nucleus, and their staining properties. This classification includes various characteristics:

1. Size: Different leukocytes vary in size. For instance, lymphocytes are typically smaller compared to monocytes.

2. Appearance of the Nucleus: The nuclei of leukocytes have distinct shapes and characteristics. For example, neutrophils have multi-lobed nuclei, whereas lymphocytes usually have a large, single nucleus.

3. Staining Properties: Each type of leukocyte responds differently to various stains used during blood smears. For example, eosinophils will stain orange-red due to their granules, while basophils will stain blue or purple.

By examining these features, hematologists can accurately identify and differentiate the types of leukocytes present in a blood sample, which is crucial for diagnosing various health conditions. This intricate classification system emphasizes the importance of morphological characteristics in understanding the immune response.