A disease breaks out among sheep in California. A scientist takes blood from the sheep and grows a previously unknown organism.
That organism is then injected into a healthy sheep. The healthy sheep becomes sick with the same symptoms as the original sheep and dies. That sheep's blood is then cultured, and the original organism is isolated. This applies the principles of __________.
The correct answer is option b) "Koch's postulates".
Koch's postulates propose four criteria used to establish that a pathogen is responsible for a disease. In his famous experiments, Robert Koch was able to prove that <em>Bacillus anthracis</em> is the cause of anthrax by injecting to a mouse an isolated culture from the blood of an injected sheep. The scenario established in the question is very similar to anthrax, and the scientific approach to look for the pathogen of the disease is following the principles of Koch's postulates.
