Chapter 11 Blood 11.3 and 11.4

Chemotaxis

What gives wbc's the ability to move through capillary walls into tissues in response to chemicals released by damaged tissues or pathogens. They follow a chemical trail through the tissue spaces to reach the source of the chemical

Granulocytes

neutrophils, eosinophils, basophils.

White blood cells (leukocytes)

A blood cell that has defensive and immune functions

Platelets

Cytoplasmic fragments of megakaryocytes (large cells that develop from hemocytoblasts in red bone marrow) Play a crucial role in hemostasis by forming platelet plugs and starting coagulation

B lymphocytes

Develop into antibody-producing plasma cells in response to foreign antigens

T lymphocytes

Directly attack and destroy pathogens (bacteria and viruses)

Eosinophils

Help to reduce inflammation and destroy parasitic worms Constitute 1% to 4% of the WBC's

Agranulocytes

Lymphocytes and monocytes

Neutrophils

Phagocyte that destroys bacteria and cleans up after cellular debris Most abundant white blood cell Attracted by chemicals released from damaged tissues and are the first wbc's to respond to tissue damage. Engulf bacteria and cellular debris by phagocytosis and release lysozyme

Macrophages

Phagocytic cells that join with neutrophils to clean up damaged tissues and pathogens. They carry out their functions of engulfing dead cells, cellular debris, and bacteria only after migrating into body tissues.

Lymphocytes

Play vital roles in immunity Form 20-40% of the circulating WBC's. They're the smallest WBC's

Basophils

Promote inflammation Least numerous of the WBC's, only forming .5% to 1%

Monocytes

The largest WBC's and they comprise 2-8% of the WBC's Phagocytosis of bacteria and cellular debris