In the early 20th century, Carl von Voit and Max Rubner independently measured caloric energy expenditure in different species of animals, applying principles of physics in nutrition. In 1906, Edith G. Willcock and Frederick Hopkins showed that the amino acid tryptophan aids the well-being of mice but it did not assure their growth. In the middle of twelve years of attempts to isolate them, Hopkins said in a 1906 lecture that "unsuspected dietetic factors," other than calories, protein, and minerals, are needed to prevent deficiency diseases. In 1907, Stephen M. Babcock and Edwin B. Hart conducted the single-grain experiment, which took nearly four years to complete. COUNT 5
QSN1 What was measured in the early 20th century? ANS1 caloric energy expenditure QSN2 What did Carl von Voit and Max Rubner apply to nutrition in order to receive their results? ANS2 principles of physics QSN3 Which amino acid can assist with the well - being of mice but not necessarily their growth? ANS3 tryptophan QSN4 What did Hopkins believe was required other than calories, protein and minerals to help prevent deficiency diseases? ANS4 unsuspected dietetic factors QSN5 Which experiment related to diet was conducted that required four years to complete? ANS5 single-grain experiment