|
|
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.
The largest baby ever born weighed more than 23 pounds but died just 11 hours after his birth in 1879. The largest surviving baby was born in October 2009 in Sumatra, Indonesia, and weighed an astounding 19.2 pounds at birth.
Although the Roman numeral for the number 4 has always been taught to have been "IV," according to historians, the ancient Romans probably used "IIII" most of the time. This is partially backed up by the fact that early grandfather clocks displayed IIII for the number 4 instead of IV. Early clockmakers apparently thought that the IIII balanced out the VIII (used for the number 8) on the clock face and that it just looked better.
The FDA recognizes 118 routes of administration.
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).
![Using the cursors on the oscilloscope, the high- and low-oxygen sensor values can be displayed on ...](https://biology-forums.com/gallery/29/medium_548020_30_05_17_10_29_36_29951684.png)
![A typical direct-injection system uses two pumps—one low-pressure electric pump in the fuel tank ...](https://biology-forums.com/gallery/30/medium_548020_31_05_17_1_51_45_30018512.png)