CIRCULATORY AND RESPIRATORY I pp 940-942

BLOOD FUNCTION Transports nutrients, O2, CO2, & waste Defends the body against disease

COMPOSITION Plasma: liquid medium Red blood cells (erythrocytes): transport CO2 and O2 White blood cells (leukocytes): defend against disease Platelets: form blood clots

PLASMA Made of 90% water, sugar, salts, amino acids, vitamins, minerals Yellow in color

PLATELETS partial cells formed in bone marrow release chemicals to attract a protein called fibrin to make clots

RED BLOOD CELLS most common in the blood made in red bone marrow made of iron-containing hemoglobin lack of nucleus leaves space to transport materials

WHITE BLOOD CELLS Form in red bone marrow but mature in the lymph nodes Many types of white blood cells

LYMPHATIC SYSTEM The human circulatory system processes an average of 20 liters of blood per day Some fluid gets trapped between cells The lymphatic system transfers that fluid to the circulatory system Stores WBCs to fight infections