August Krogh
Facts
Schack August Steenberg Krogh
The Nobel Prize in Physiology or Medicine 1920
Born: 15 November 1874, Grenå, Denmark
Died: 13 September 1949, Copenhagen, Denmark
Affiliation at the time of the award: Copenhagen University, Copenhagen, Denmark
Prize motivation: “for his discovery of the capillary motor regulating mechanism”
Prize share: 1/1
Life
August Krogh was born in Grenå, Denmark, where his father worked as a shipbuilder. He studied medicine and zoology at the University of Copenhagen and, in 1897, began working for physiologist Christian Bohr in Bohr's laboratory. Krogh maintained ties with the University of Copenhagen until his retirement in 1945. Though retired, he continued researching in his own private laboratory for several years. Krogh carried out much of his work in collaboration with his wife, Marie. August and Marie Krogh had four children.
Work
One of the circulatory system's most important functions is carrying oxygen to muscles. Krogh developed methods for precisely measuring blood oxygen levels and explained how oxygen supply to muscles is regulated based on workload. Previously, it was thought that it was the blood's rate of flow that increased during exertion. During the 1910s, however, Krogh showed that it was rather oxygen flow that was regulated by the opening of smaller blood vessels, capillaries. When resting, relatively few capillaries are open.
Nobel Prizes and laureates
Six prizes were awarded for achievements that have conferred the greatest benefit to humankind. The 12 laureates' work and discoveries range from proteins' structures and machine learning to fighting for a world free of nuclear weapons.
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