The human heart beats about 100,000 times a day. That works out to be about 35 million times a year and around 3 billion times in the average lifespan. That's one strong muscle!
Our organs are what keep our bodies going every day, but how much do you really know about them?
Do you know how twins or blue eyes occur? Take this quiz and see how much you know about genetics!
Information is crammed into our heads in school. How much did you retain from science class?
You live in your body 24 hours a day, but how much do you really know about it?
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