Chapter 1 and 2Cellular bio is technology driven. Microscope, centrifuge, radioactive labels, electrophoresis andgenetic engineering are all used. If any of these techniques improve, there will be an increase of knowledgeThe cellThe prokaryotic cell has a simple structure but lots of complexity in its molecular organization. The eukaryotic cell has a complex organization. Eukaryotic cells are larger than prokaryotes (40mm vs. 1mm). Eukaryotes are hybrids because they utilize separate lineages with mitochondria and chloroplasts.HistoryA microscope was needed to see cells to begin with. Later, other tools were added. The first microscope was invented in the 17th century by Robert Hooke. AN English engineer and architect, Hooke saw and named cells in 1665 from a sample of cork. He wanted to know why cork floats so sliced it very thinly and looked at it from a microscope. Surprise! It’s full of air pockets where the living cells used to be. The squares reminded him of a medieval monastery floor plan. Each monk had his own little room called a cell. Antony van Leeuwenhoek was a Dutch businessman in the late 17th century. He sold cloth and made his own microscopes. He made extensive discoveries and descriptions of protozoa, bacteria and fungi. He ground his own lenses which were vastly superior to any other kind of glass being produced at that time. He was curious about halitosis so he looked at his ownteeth and his neighbor’s. First to see spermatozoa. He wrote reports to the Royal Society in London where Hooke would present them.In the 18th century, microscopes were regarded as curiosities and little more than scientific toys. The quality of the glass and lenses was poor and gave very crude images. Scientists tried to do some really weird stuff to make the image better like putting a microscope on top of another microscope. This led to very strange conclusions, like the homunculus in a sperm cell.In the early 19th century, advances in optics and construction of optics (like the development of achromatic lenses which were special kings of glass in one lens that handles different wavelengths) produced vastly improved microscopes and images. The scientist also had to be an artist to capture and draw the images found by the microscope.Cell TheoryThe Cell Theory was developed by Mattias Sschleiden, a botanist, and Theodo Schwan, azoologist. Both German scientists were both seeing some of the same fundamental things in their research. They developed the Cell Theory in 1839All organisms are made of cells-ie an organism either is a cell or can be subdivided into morecellsCell is the fundamental unit of life-if its smaller it isn’t aliveRudolf Virchow, a German pathologist, refined their cell theory in 1855.Modern cells arise only by the division of preexisting cells.The late 19th century saw the development of staining protocols to make cell components visible through color contrast which was needed even with the best optics. For example hematoxylin and feulgen, a DNA staining substance that is also qualitative, that is the intensity depend on the amount of DNA present. Apochromatic optics were developed. These took the resolution and visualization of microscopes to the theoretical limits of visible light. E.B. Wilson wrote the first cell biology text, The Cell in Development and Heredity 1896, which was used well into the 1920’s (base of embryology, Mendel only rediscovered in 1902). Walter Flemning described mitosis/meiosis and chromosomes. Theodor Boveri published (about 1900-10) a seriesof significant papers on cells in genetics and chromosomes and heredity; and the importance of centrosomes. He studied sea urchin embryos. August Weisman studied the significance of cells and nuclei in heredity, development and EVOLUTION. If the cell is a central aspect of life, thesekinds of processes must occur and it must have this roll in later life.The 1930’s. Zernike discovered Phase Contrast Optics which allowed increased resolution and contrast images of organelles in LIVING cells. This development allowed scientists to see how the cell works over time. This was followed by Nomanski’s Differential Interference Contrast Optics (DIC) in the 1950’s, this was an even more sophisticated version of Zernike’s work. The ultracentrifuge was also developed. This centrifuge spun at about 10,000 times the force of gravity and allowed the development of protocols of cell fractionation. This allowed for the separation of individual organelles.After World War II, radioactive isotope labels were available. These labels highlight specific molecules that can be traced through the structural and metabolic pathways of a cell. The electron microscope was made. It is better than a standard microscope because electrons have a much shorter wavelengths than normal light, allowing for a finer resolution. It also convincingly showed organelles that were not visible to a light microscope. Electrophoresis is the separation and analysis of classes of proteins and nucleic acids based on size.1970’s to Present. Molecular and Genetic engineering allow for the addition or subtraction of genes or their expression and allows for the manipulation of sophisticatedorganelles. “Gene Chips” allow for the screening for expression of several thousand genes at once. Genomics is the study/comparision of gene sequences. Proteonics is the study/comparision of proteins of a cell.The Cell-Fundamental Unit of LifeThere are two prokaryote domains; archaea and bacteria. Archaea were originally thought to only live in exotic environments like thermal vents. They look like bacteria and are actually berywidespread. They probably represent very ancient forms and we don’t know a lot about them because they’re hard to grow in a lab. Bacteria are very familiar. They are easy to culture; just slap some on an agar plate and they’re happy!Eukaryotes have three main kingdoms; Animalia, Fungi and Pantae. There are also several protist groups. Archaea are closer to eukaryotes than to bacteria. There are other cell like forms that aren’t technically alive. Viruses can’t reproduce on their ownso they aren’t alive. They have either DNA or RNA, but NEVER both, and protiens. A viroid is a small piece of naked RNA; they often attack and disrupt plant cell metabolism. Prions are infectious, abnormal proteins. They are classified by the ability to change how a normal protein