The most frequently occurring leukocytes are?

The most frequently occurring leukocytes in the bloodstream are neutrophils, which typically make up about 55-70% of the total white blood cell count. They play a crucial role in the immune response by responding rapidly to infections, particularly bacterial infections. Other types of leukocytes include lymphocytes, monocytes, eosinophils, and basophils, but neutrophils are the predominant type.