Blood is the life-giving fluid that delivers oxygen to the cells of the body. It is a specialized type of connective tissue that consists of red blood cells, platelets, and white blood cells suspended in a liquid plasma matrix. These are the basics, but there are many more surprising facts as well; for example, blood accounts for about 8 percent of your body weight and it contains trace amounts of gold.

Intrigued yet? Read on below for more fascinating facts.

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• Blood makes up around 7% of the weight of a human body.
• Blood is about 45 % cells & 55 % plasma.
• Red blood cells develop in bone marrow and have life span of  120 days.
• Plasma is 90 % water and human blood is 83% water.
• Amazingly a Newborn baby has just about 1 cup of blood in his body.
• Amazing fact is that a drop of blood contains  about 250 million cells.
• Amazing thing is that the capillaries are so small that it would take ten of them to equal the thickness of a human hair.
• The fact is that all the blood in our body passes 400 times through each kidney per day.
• Red Blood Cells are the only cells in the body that amazingly doesn’t have a nucleus.
• Lacking the nucleus, each red blood cell has more room to carry the oxygen the body needs. But without a nucleus, the cells cannot divide or synthesize new cellular components.
• In 24 hours, the blood in the body travels a total of 12,000 miles , amazingly that’s four times the width of North America.
• Amazing fact is that there are 60,000 miles ( 100000 km) of blood vessels in the human body enough to circle the earth 2.5 times which has 25000 miles ( 40000 km) circumference.
• Each red blood cell lives about 4 months and travels between the lungs and other tissues 75,000 times before returning to the bone marrow to die.
• Your body is creating and killing amazing 15 million red blood cells per second.
• One pint of donated blood can save three lives.
• Someone needs blood every two seconds.
• There are 4 types of blood. O , A , B and AB. Each type cab be Rh positive (Rh +) or Rh negative (Rh -ve).
• Amazing fact is that normal blood sugar is just equivalent to about a teaspoon dissolved in your entire volume of blood.
• Corn starch (a common thickening agent in foods), will spike your blood sugar level faster than pure sugar.
• These groups were identified first time by Karl Landsteiner in 1901.
•  85 % of Americans have Rh +ve blood. In contrast, 99 % of Chinese have Rh +ve blood.
• Amazing fact is that Cows have more than 800 blood types in contrast to just 4 types in humans. Dogs have 4 types of blood while a cat has 11 types of blood.
• AB +ve blood is a universal recipient of blood. It can receive any type of blood.
• June 14 was chosen as World Blood Donor Day as it was the birthday of Karl Landsteiner (1868-1943) who won the Nobel prize in 1930 for his discovery of human blood groups.
• One out of every 10 people admitted in a hospital needs blood.
• O –ve blood is a universal donor. It can be given to any blood type.
• Every 2 seconds somebody in US needs blood. About 38000 blood donations are needed every day in US.
• There are about 40 diseases which may be cured from stem cells of cord blood for self and immediate family members. Cord blood with rich quantity of stem cells may be preserved for years.
• Mosquitoes prefer blood type O to any other.
• The world’s first blood bank was opened in Chicago in 1936.
• Red Cross supplies 40 % of the blood supply in US.
• It is surprising that less than 10 % people donate blood annually. If every eligible donor donates blood thrice a year , there wouldn’t be blood shortage.
• Estimated 1.3 million pints of donated blood spoil every year since as blood has only 42-day shelf life in cold storage. Frozen plasma can be stored for one year.
• Amazingly the liquid inside coconuts can be used as blood plasma substitutes!
• Your nose runs when it’s cold because the blood vessels in the nose get more blood to keep
• After 9/11 and the flood of blood donations, the Red Cross had to throw out all of the surplus blood after 42 days and experienced a shortage of blood.

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