« previous next »
« previous next »
 

Did you know?

In ancient Rome, many of the richer people in the population had lead-induced gout. The reason for this is unclear. Lead poisoning has also been linked to madness.

Did you know?

The National Institutes of Health have supported research into acupuncture. This has shown that acupuncture significantly reduced pain associated with osteoarthritis of the knee, when used as a complement to conventional therapies.

Did you know?

Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.

Did you know?

Approximately one in three babies in the United States is now delivered by cesarean section. The number of cesarean sections in the United States has risen 46% since 1996.

Did you know?

The top five reasons that children stay home from school are as follows: colds, stomach flu (gastroenteritis), ear infection (otitis media), pink eye (conjunctivitis), and sore throat.

Rusty-tipped Page (Siproeta epaphus), Butterfly World (Florida) Rusty-tipped Page (Siproeta epaphus), Butterfly World (Florida)
Worldwide Variations in Population and Income Levels Developed countries represent only 18% of the Worldwide Variations in Population and Income Levels Developed countries represent only 18% of the
A water spray bottle is an excellent diagnostic tool to help find an intermittent engine misfire ... A water spray bottle is an excellent diagnostic tool to help find an intermittent engine misfire ...
World Crude Oil Production, 1900–2010 World Crude Oil Production, 1900–2010
A 400-g piece of metal at 120°C is dropped into a cup containing 450 g of water A 400-g piece of metal at 120°C is dropped into a cup containing 450 g of water
A thimble of water contains 4.0 x 1021 molecules. The number of moles of H2O is: A thimble of water contains 4.0 x 1021 molecules. The number of moles of H2O is:
Video: How to find out if a population is evolving?

For a complete list of videos, visit our video library