LETTER

Transports most oxygen and some carbon dioxide in blood

cell fragments that form a plug and release vasoconstrictors during hemostasis

Phagocytic granular leukocytes; most numerous leukocytes

Intensify inflammatory response via release of histamine and serotonin

combat effects of histamine in allergic reactions

develop into plasma cells that secrete antibodies

attack viruses, cancer cells, and transplanted cells

develop into macrophages outside of circulation

form of RBC that enters circulation from the bone marrow; serve as indicators of rate of erythropoiesis

precursor for blood cells