Did you know?

The immune system needs 9.5 hours of sleep in total darkness to recharge completely.

Did you know?

Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.

Did you know?

There are over 65,000 known species of protozoa. About 10,000 species are parasitic.

Did you know?

When Gabriel Fahrenheit invented the first mercury thermometer, he called "zero degrees" the lowest temperature he was able to attain with a mixture of ice and salt. For the upper point of his scale, he used 96°, which he measured as normal human body temperature (we know it to be 98.6° today because of more accurate thermometers).

Did you know?

After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.

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