A virus is a minute infectious agent that, in general, cannot be seen with a light microscope. It lacks an independent metabolism and is able to replicate only within a living host cell. A free virus particle does not carry out the functions of a living cell, such as respiration and growth, and may be thought of as a packaging device by which viral genetic material can be introduced into appropriate host cells. What are the arguments for and against classifying viruses as living organisms?
Back in the day
The establishment of a permanent US Navy came with the authorization to build six frigates in 1794. Three of these were welcomed into service soon thereafter and distinguished themselves in the War of 1812 by unexpectedly defeating British Royal Navy forces several times. The US Navy currently has nearly 500,000 personnel on active duty or in the Navy Reserve and operates 278 ships in active service and more than 4,000 aircraft. What role did naval power play in the American Civil War?
Born on a day like today
English scientist and professor of mathematics Karl Pearson was an instrumental figure in the development of mathematical statistics. In 1911, he became professor of eugenics at the University of London and director of the eugenics laboratory. A disciple of Francis Galton, he applied statistical methods to the study of biological problems, especially evolution and heredity, in a science he called biometrics. Today, Pearson's views on eugenics are considered deeply racist; why?