10 Remarkable Blood Facts from the “Incredible Machine”
By John Haberstock 12 Jun 2019
Here are 10 remarkable facts about blood from the “Incredible Machine.”¹
- Human blood retains a link to ancient Cambrian seas: The same balance of salts and minerals that existed in primitive oceans half a billion years ago is present in blood.
- Blood is a liquid tissue: Fluid makes up more than half while plasma, white, and red blood cells make up the remainder.
- The heart expels 2 ounces of blood with each beat, 5 quarts of blood each minute and 8,610 quarts per day.
- Red blood cells (erythrocytes) are the body’s cellular lungs. Their job is to ferry oxygen to every cell and remove carbon dioxide.
- If the red blood cells from one person were to be stacked, they would reach 31,000 miles high.
- Each red blood cell has 270 million hemoglobin molecules. Each hemoglobin molecule can carry four oxygen molecules.
- The hemoglobin in red blood cells scoops up oxygen molecules in oxygen-rich tissues, such as the lungs, and the releases them in oxygen-deprived tissues throughout the body.
- Each second, we lose about 3 million red blood cells only to be replaced by the same number produced in the bone marrow.
- Venous blood that delivers carbon dioxide back to the lungs makes up 75% of blood volume at any given moment.
- Blood flow measurement is vital because it provides a window into the delivery of oxygen and nutrients to body organs and cells. To measure is to know!
¹The Incredible Machine 1992 National Geographic Society, Washington, DC