Chapter 11 The Blood 325 Copyright Goodheart-Willcox Co., Inc. Formed elements Plasma (55%) White blood cells and platelets (1%) Red blood cells (45%) (hematocrit) Red blood cells (erythrocytes) White blood cells (leukocytes) Functions of the formed elements Blood draw Centrifuge Cell type 150,000–440,000 4,000–11,000 4–6 million Number per μL (mm3) of blood Functions Carry oxygen and carbon dioxide Immune response– fight infection, produce antibodies, and intensify inflammatory response Form and dissolve blood clots Basophil Neutrophil Eosinophil Lymphocyte Monocyte Platelets Tyler Olson/Shutterstock.com Ideya/Shutterstock.com Buffy coat © Body Scientifi c International Figure 11.3 Blood is drawn into tubes that are then centrifuged to separate the formed elements from the liquid component of blood.