In Lesson 13, Sir Alexander Fleming, the author Patrick Pringle discusses the revolutionary contributions of Louis Pasteur and Joseph Lister to the field of medicine. Pasteur’s discovery of microscopic living organisms, commonly referred to as germs or microbes, laid the foundation for understanding the cause of diseases. Lister, an English surgeon, applied Pasteur’s findings by developing antiseptic methods in surgery.
Lister’s approach aimed at preventing disease by eliminating germs from the surgical environment. He used carbolic acid to sterilize surgical instruments, cleanse hands, and sanitize the operating theater. By doing so, Lister significantly reduced the risk of patients being infected during surgical procedures.
While Lister’s antiseptic methods focused on preventing the entry of germs into the body, the challenge remained in treating diseases where germs were already inside. Attempts to use chemicals like carbolic acid to kill germs internally proved harmful to the body’s cells, and more drastic measures risked harming the patient.
The author introduces Metchnikoff, a bacteriologist and pupil of Pasteur, who unveiled a crucial aspect of the problem. Metchnikoff discovered the body’s natural defense against diseases: the white blood cells, or leucocytes. These cells actively combat germs, rushing to the site of infection to engage in a battle for survival. Disease, as Metchnikoff revealed, is essentially a confrontation between the body’s white blood cells and invading germs, with the outcome determining the patient’s fate—either the death of the germs or the death of the patient.
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- Chapter No. 16 Support and Movement 2nd Year Biology
- Chapter No. 17 Coordination and Control 2nd Year Biology
- Chapter No. 18 Reproduction 2nd Year Biology
- Chapter No. 19 Growth and Development 2nd Year Biology