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Unit 6: Hematologic system physiology and disease
About this unit
It takes 30 to 60 seconds for your blood to travel from your heart to your body and back again. Hemoglobin, the protein in our blood cells, can bind oxygen and carbon dioxide. Blood is about 45% cells and 55% plasma, so the adage “blood is thicker than water” holds true in scientific terms! Learn more about how this system works in these videos.