In my quest to plug all the gaps in my education, I'm now studying Biology as part of my 2-year part-time course in Life Sciences at Birkbeck. This is roughly equivalent to A-Level Biology, and is no less daunting a subject than when I chose to brush it aside at 16. Part of the difficulty that I find in tackling sciences is coming to terms with the very small; last year with Chemistry it was the atom, now it's the cell. Another drawback has always been my clumsiness with scientific equipment, but this time round at age 30 I've finally got the hang of bunsen burners and microscopes. So, with plenty of hard work and a more considered approach, I'm finally getting a handle on many of the abstract concepts, the strange terminology and miniscule machinations of the cells and atoms in and around me, and here I'm sharing my findings with the blog.
Microscopes first came into existence in the 1600s. Antoine van Leeuwenhoek, a linen merchant from Delft, was first to observe cells. He was also first to examine sperm and red blood cells up close. Like many discoveries in science, this came about by accident owing to technological advances in another area - in this case refining microscopic lenses (up to 500 times) to view linen fibres up close. Fellows of the Royal Society were sceptical, and Robert Hooke was commissioned to examine the claims. In his own research and his landmark work, Micrographia, he was first to use the word cell to describe the self-contained units of living organisms. Van Leeuwenhoek was proved right and became one of the most celebrated men in Holland. Together, the two men became the hook on which to hang biology's rich tapestry.
In 1830, Robert Brown (he of Brownian motion) discovered the nucleus at the heart of every cell, so was unique in making significant breakthroughs in both biology and physics.
JJ Lister, Joseph Lister's father, refined microscopes further in the 1830s by combining convex and concave lenses, to produce microscopes with better colour clarity that could examine both animal and plant cells. This led to the development of cell theory in 1838 by the Germans, Schwann and Schleiden. Cell theory, like evolution and DNA, is one of the cornerstones of biology - however there was a fatal flaw in S&S's cell theory, i.e. the belief in spontaneous generation of cells. Any budding biologist will tell you that one of the key components of cell theory is that new cells can only be generated from pre-existing cells.
JJ Lister, Joseph Lister's father, refined microscopes further in the 1830s by combining convex and concave lenses, to produce microscopes with better colour clarity that could examine both animal and plant cells. This led to the development of cell theory in 1838 by the Germans, Schwann and Schleiden. Cell theory, like evolution and DNA, is one of the cornerstones of biology - however there was a fatal flaw in S&S's cell theory, i.e. the belief in spontaneous generation of cells. Any budding biologist will tell you that one of the key components of cell theory is that new cells can only be generated from pre-existing cells.
It was Louis Pasteur in the 1860s who finally disproved the medieval bunkum of spontaneous generation. By creating swan neck flasks, he was able to eliminate microbes from his experiment, and produce a sterile environment where no new cells could form. This was an important breakthrough, however the question of how cells first originated from inorganic matter (abiogenesis) still remains open to debate today. Nevertheless, key advances such as the synthesis of the genetic ideas of Mendel and the evolutionary theory of Darwin to launch modern biology, as well as the discovery of DNA in the 1950s, mean we are much closer to finding out an answer. This would herald what is called the second genesis, and right now there are biologists working away in Harvard and Cambridge, most notably George Church, who are close to building a biological cell, just like a car, from its constituent parts.
All pretty frightening or pretty exciting, depending on your point of view, and my main objective in doing this course is to better understand all the biological processes that underpin the cell and life itself. No pressure then.
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