By *1900* scientists were aware that *genes* came in *pairs*, and that one was *inherited* from each *parent*, and by *1951* they knew that characteristics were passed down from *parents* to *children*
For centuries people had been aware of the need for a *balanced diet*, but in the *20th century* Doctors became particularly concerned about *sugar* and *fat* as the cause of widespread diseases such as *diabetes*.
By *trial and error* - he tested *600 arsenic compounds* to try to find a cure for *Syphilis*. He failed, but in *1909* a Japanese scientist, *Hata*, *retested* them and found that compound *606* did cure *syphilis*.
He discovered that *Prontosil* killed bacterial infections in *mice*. He successfully used this to treat his own *daughter* for *blood poisoning**. *Other magic bullets* were discovered through the *1930s*.
In *1920* Alexander Fleming isolated a substance called penicillin from a *mould sample* in his lab which appeared to *kill* a wide range of *bacteria* - he had noticed that bacteria would not *grow* near the *mould*
Because they knew that *infected wounds* killed thousands of soldiers. If these soldiers could be successfully *treated* they would be able to *rejoin the fight*. This would give them an *advantage* over the enemy
By the *end of World War II* it was possible to treat *all* allied casualties with *penicillin*, and this had a huge impact on *survival rates*, mainly because soldiers were no longer *dying* from *infected wounds*
By *1900* governments were already more willing to *take responsibility* for the health of the population, but from *1948* this role increased massively when the *NHS* was set up. This is paid for and managed by the *government*
*Penicillin* had been discovered in *1920*, but it was not until *World War II* that the American and British *governments* were prepared to pay the huge amounts of *money* that were needed to produce *enough* penicillin to *treat* large numbers of people