Gertrude Belle Elion was a biochemist that has discovered many treatments and medications for various illnesses. Although, she wasn't able to be a scientist with a Ph. D, she still went through life treating sickness.
Elion went through many tough times because she was a women scientist. She was denied many times from chemistry labs and jobs because of her gender. From the disappointing rejections, she had to teach nurses biochemistry to earn enough money for graduate school.
Even after graduate school, she wasn't able to get a chemistry job until WWII. This war opened up jobs because of the loss of men, and now Gertrude was able to start her "dream job".
Her prestigious work ethics helped to treat many illnesses like gout, herpes, leukemia, malaria, and the rejection of transplanted organs. Also, a few years after she retired, her work carried on the help treat AIDS.
I have also been told many times that biology is too hard, and it is a competitive study. That's why I chose Gertrude.She was able to get through the sexist laboratories to then discover very important treatments for the world. It is quite ironic how she was denied because of the stigma of women, and then she goes on to win a Noble Peace Prize while creating many treatments.