A citrate is a derivative of citric acid; that is, the salts , esters , and the polyatomic anion found in solution. An example of the former, a salt is trisodium citrate ; an ester is triethyl citrate .
If a bacterium cannot use citrate agar will not change its color (stays green). On the other hand, if bacteria have the ability to use citrate, the medium will change its color from green to blue.
This happens because citrate agar contains pH indicator such as bromothymol blue which transforms from green to blue in alkaline conditions.
Base on the given scenario, a sociologist might view the
doctor’s recommendation as a result of belief in a binary sex system of which
the social norm is about in terms of topics related with the gender and sex of
humans and the doctors recommendations are all because of their beliefs and
perspectives that they had acquire.