1. Types of White Blood Cells
Are leukocytes
Protect against disease
WBC hormones are interleukins and colony-stimulating factors which stimulate development
There are five types of WBCs in two categories:
Granulocytes
Neutrophils
Eosinophils
Basophils
Agranulocytes
Lymphocytes
Monocytes

2. Neutrophils Light purple granules in acid-base stain Lobed nucleus
Other names
Segs
Polymorphonuclear leukocyte
Bands (young neutrophils)
First to arrive at infections
Phagocytic
54% - 62% of leukocytes
Elevated in bacterial infections
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
© Ed Reschke

3. Eosinophils Deep red granules in acid stain Bi-lobed nucleus
Moderate allergic reactions
Defend against parasitic worm infestations
1% - 3% of leukocytes
Elevated in parasitic worm infestations and allergic reactions
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
© Ed Reschke

4. Basophils Deep blue granules in basic stain Release histamine
Release heparin
Less than 1% of leukocytes
Similar to eosinophils in size and shape of nuclei
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
© Ed Reschke

5. © R. Kessel/Visuals Unlimited
Monocytes
Largest of all blood cells
Spherical, kidney-shaped, oval or lobed nuclei
Leave bloodstream to become macrophages
3% - 9% of leukocytes
Phagocytize bacteria, dead cells, and other debris
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
© R. Kessel/Visuals Unlimited

6. Lymphocytes Slightly larger than RBC
Large spherical nucleus surrounded by thin rim of cytoplasm
T cells and B cells
Both important in immunity
B cells produce antibodies
25% - 33% of leukocytes
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
© Ed Reschke

7. Functions of White Blood Cells
WBCs protect against infection
These leukocytes can squeeze between the cells of a capillary wall and enter the tissue space outside the blood vessel (called diapedesis)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Connective
tissue
Blood capillary
Leukocyte