Copenhagen: United States scientists Jeffrey C. Hall, Michael Rosbash and Michael W. Young have been awarded the 2017 Nobel Prize in Medicine for their discoveries relating to the biological clock, the Nobel Assembly at Karolinska Institutet in Stockholm said Monday.

Their award-winning scientific discovery explains how plants, animals and humans adapt their biological rhythm so that it is synchronized with the Earth’s revolutions, a phenomenon also known as the circadian rhythm, Efe reports.

‘For many years we have known that living organisms, including humans, have an internal, biological clock that helps them anticipate and adapt to the regular rhythm of the day,’ the Nobel assembly said in a statement. ‘But how does this clock actually work? Jeffrey C. Hall, Michael Rosbash and Michael W. Young were able to peek inside our biological clock and elucidate its inner workings,’ it added.

The expression circadian rhythm originates from the Latin words circa meaning ‘around’ and dies meaning ‘day’.

But just how our internal circadian biological clock worked remained a mystery.

The Nobel Assembly said their decision was based on the scientific trio’s breakthrough that showed ‘using fruit flies as a model organism, they had isolated a gene that controls the normal daily biological rhythm’ and added that ‘they showed that this gene encodes a protein that accumulates in the cell during the night, and is then degraded during the day.

The ‘clock’ regulates critical functions such as behaviour, hormone levels, sleep, body temperature and metabolism,’ the statement said.

Subsequently, the three Nobel winners identified additional protein components of this machinery, exposing the mechanism governing the self-sustaining clockwork inside the cell.

Hall was born in New York in 1945 and works at the University of Maine; Rosbash was born in Kansas in 1944 and works at Brandeis University in Waltham, Massachusetts, while Young, was born in Miami in 1949 and works at the Rockefeller University in New York.

The award includes 9 million Kronen, to be shared among the three winners and reflects a Nobel prize increase for the first time in five years.

The next Nobels to be announced will be the Physics and Chemistry awards on Tuesday and Wednesday while the Literature award will be known on Thursday.

The Peace prize will be revealed on Friday and then the Economy award will be announced on Monday.

All awards are announced in Stockholm except the Peace Prize that is selected and awarded in Oslo, by express request of the Award’s founder, the Swedish industrialist Alfred Nobel (1833-1896), as during his lifetime Norway belonged to the Swedish Crown.

The awards ceremony is due to take place on December 10, coinciding with the anniversary of Nobel’s death during a traditional joint ceremony at Stockholm’s Konserthus and Oslo’s Town Hall.