|
|
The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
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).
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
Acute bronchitis is an inflammation of the breathing tubes (bronchi), which causes increased mucus production and other changes. It is usually caused by bacteria or viruses, can be serious in people who have pulmonary or cardiac diseases, and can lead to pneumonia.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.