Category Great Scientific Discoveries

          Though Robert Hooke coined the term ‘cell’, Theodor Schwann and Matthias Jakob Schleiden are accredited with the first cell theory for their work in the 1830s.

          The cell theory states that living things are composed of cells, be it unicellular or multicellular; cells are the basic unit of life and cells arise from existing cells. Although Schleiden and Schwann proposed that cells arise through spontaneous generation, this was proven wrong.

The accepted tenets of modern cell theory are as follows:

1. Cells are the fundamental units of structure and function in all living things.

2. All organisms are made up of one or more cells.

3. Cells arise from pre-existing cells through cellular division.

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        In the year 1859, Charles Darwin, a doctor’s son, shook the world with the publication of a book. The book, titled, On the Origin of Species, claimed with supporting evidence that plants and animals evolved from earlier forms and are still evolving. Darwin’s work opposed the belief that animals and plants were created as we see them today.

          His theory of evolution is based on the idea of natural selection. Though the members of a species have many similarities, each one is slightly different from the other. The differences that some members possess help them survive by competing with the others. And the traits that helped them survive are passed on to their offspring.

          Darwin observed the differences between the finches on various Pacific Islands and studied fossil records. The concept of natural selection came to him after reading an essay by Thomas Malthus in which Malthus said that animals compete to survive. Darwin realised that such a competition can explain the evolution of animals.

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          In the olden days, surgeries and other medical treatments were conducted without administering pain killers. The patient had to suffer severe pain to get the treatment done. Surgeons and doctors worked to discover sedatives that would numb the patient’s body, so that the surgery would be painless, or rather less painful.

          Two American dentists, Horace Wells and William Morton were the first to use anaesthetics. Wells made an unsuccessful attempt to use laughing gas (nitrous oxide) in 1845 in addition to trying if ether would act as a local anaesthetic. Morton tried making his patients inhale ether and successfully demonstrated anaesthetic surgery in 1846.

          Next year, a Scottish surgeon James Simpson started using chloroform to help women through the pain of childbirth. He attained immense popularity after giving chloroform to Queen Victoria during the birth of Prince Leopold, her eighth child.

         Much safer and effective alternatives to sulphuric ether and chloroform are available today. Mainly sevoflurane and isoflurane are used as anaesthetics. General anaesthesia is considered as one of the greatest discoveries of all time.

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          The work of ancient Greek physician Galen formed the basis of what doctors knew about human anatomy for centuries. However, Andreas Vesalius, a 16th century Flemish physician, approached the structure of the human body from a fresh perspective.

          Until then, dissection of human bodies was not used in the study of human anatomy; most of Galen’s studies were based on dissection of animals. Unlike his predecessors, Vesalius dissected human bodies and conducted his studies through direct observation.

          His discoveries were recorded and published in 1543 titled De Humani Corporis Fabrica, his masterpiece. This work revolutionized medical science and laid the foundation for research on modern human anatomy. Consequently, Vesalius came to be considered as the founder of studies on modern human anatomy.

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          During the mid-19th century, humans had still not discovered the science behind some natural processes. For instance, what turned grape into wine? And why did it acquire a sour taste?

          A French chemist, Louis Pasteur, found that microorganisms are responsible for this. He also proved that, rather than polluted air, diseases were transmitted by these invisible organisms. Before Pasteur, invasion by invisible organisms were thought to be responsible for decay and disease.

         In 1864, the French Academy of Sciences officially accepted Pasteur’s conclusions. Three years later he was provided with his own laboratory in France’s Ecole Superieure, a graduate school in Paris. Pasteur’s ‘germ’ theory soon received wider acceptance. He revolutionized medicine and the food industry by establishing the reality of germs. He also developed the earliest vaccines against fowl cholera, anthrax, and rabies. Pasteur became a household name after he invented the technique for treating milk and wine to prevent bacterial contamination. This process is now called pasteurization.

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          A Hungarian doctor named lgnaz Semmelweis once asked the medical students at Vienna’s maternity hospital to disinfect their hands. He had proved that this made their presence in labour rooms less dangerous. But this offended his superiors and he was dismissed from service. This happened in 1849.

          The indifferent attitude towards disinfecting continued well after 1864 when Louis Pasteur’s germ theory was accepted in France. Most surgeons continued operating without even changing into clean clothes.

          However, things began to change in 1867 when Joseph Lister published the paper “Antiseptic Principle of the Practice of Surgery”. Lister was inspired by Louis Pasteur’s germ theory of putrefaction. He advocated the use of carbolic acid, which is a powerful germ killer to disinfect. He had already begun putting this into practice in his operating theatres and on to dressings by 1865. Lister’s introduction of antiseptic surgical methods paved the way for modern sterile surgery.

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