« previous next »
« previous next »
 

Did you know?

Asthma attacks and symptoms usually get started by specific triggers (such as viruses, allergies, gases, and air particles). You should talk to your doctor about these triggers and find ways to avoid or get rid of them.

Did you know?

Liver spots have nothing whatsoever to do with the liver. They are a type of freckles commonly seen in older adults who have been out in the sun without sufficient sunscreen.

Did you know?

During the twentieth century, a variant of the metric system was used in Russia and France in which the base unit of mass was the tonne. Instead of kilograms, this system used millitonnes (mt).

Did you know?

The tallest man ever known was Robert Wadlow, an American, who reached the height of 8 feet 11 inches. He died at age 26 years from an infection caused by the immense weight of his body (491 pounds) and the stress on his leg bones and muscles.

Did you know?

In 1864, the first barbiturate (barbituric acid) was synthesized.

Feral pigs in the United States (here Cape Canaveral, Florida) Feral pigs in the United States (here Cape Canaveral, Florida)
Cartoon of Uncle Sam teaching states in Puck Cartoon of Uncle Sam teaching states in Puck
High rates of rural poverty have been a part of the United States from its origin to the present. ... High rates of rural poverty have been a part of the United States from its origin to the present. ...
Leading Sites of New Cases of Cancer in the United States, 2013 Leading Sites of New Cases of Cancer in the United States, 2013
States that require licensing or certification. Graphic provided by Associated Bodywork & ... States that require licensing or certification. Graphic provided by Associated Bodywork & ...
Age structure for the United States Age structure for the United States
Video: Gas exchange - driving force

For a complete list of videos, visit our video library