Why Is Blood Pressure Two Numbers?
Blood pressure might better be called heart pressure, for the heart's pumping action creates it. To measure blood pressure, health workers determine how hard the blood is pushing at two different times: when the heart contracts, called systole; and when the…
Continue reading →
More science facts
Biology
A Tickle is All in the Timing
It's often been noted that no matter how hard you might try, you can't tickle yourself. Why not? Whether it's…
Biology
The Great Permian Extinction
More than 250 million years ago, when the current continents formed a single land mass, known as the Pangea…
Biology
Nematodes Are Everywhere
Nematodes are simple worms consisting of an elongate stomach and reproduction system inside a resistant outer…
Astronomy
Mount Olympus
Olympus Mons, the largest volcano in the solar system, towers a breathtaking 25 km above the surrounding…