Mosquitoes don't just bite you, they also pee on you.
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Mosquitoes prefer certain blood types, and people with the “O” blood type are more likely to get bitten.
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Your body is creating and killing about 2.4 million red blood cells per second.
17
Lobsters have blue blood.
476
Your heart will pump about 212 million liters in its lifetime.
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From the nitrogen in our DNA, to the calcium in our teeth, the iron in our blood, to the carbon in our apple pies - all were made in the interiors of collapsing stars; we're all made of stardust.
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Consumption of TNT turns urine amber or deep red, which people often mistake for blood.
301
If a vampire bat goes 2 days without drinking blood, they can die. However, well fed female bats will puke up blood and share it with other bats that they like in exchange for grooming.
13