section_path: Constituents/In mammals
section_name: In mammals
paragraph_text: In mammals
  
  Blood accounts for 7% of the human body weight, with an average density around 1060 kg/m, very close to pure water's density of 1000 kg/m. The average adult has a blood volume of roughly 5 litres (11 US pt) or 1.3 gallons, which is composed of plasma and formed elements. The formed elements are the two types of blood cell or corpuscle – the red blood cells, (erythrocytes) and white blood cells (leukocytes), and the cell fragments called platelets that are involved in clotting. By volume, the red blood cells constitute about 45% of whole blood, the plasma about 54.3%, and white cells about 0.7%.
  
  Whole blood (plasma and cells) exhibits non-Newtonian fluid dynamics.