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Bacteria An Actual Report Essay Research Paper

Bacteria comes from the Greek word meaning “Little Staff” (Infopedia) (or more appropriately “Staph”) which most likely refers to some form of Bacillus, but what is bachteria and why do we need it. When most people think of the idea of little crawlies on their skin, they pretty much freak (See Jackie Plank), but we need to see is the difference between the pathogens and the helpful bacteria, the good and the bad, the yin and yang of monerans.

Koch (1843-1910) is often considered the founder of medical bact eriology. A german scientist and Nobel laureate he managed to discover several pathogens including tuberculosis, and discovered the animal vectors of a many of major diseases. (Encarta 95)

Koch was born in Klausthal-Zellerfeld, December 11, 1843; in 1862 Koch began his education at the University of Gottingen. He studied mostly botany, physics, and mathematics and so began his medical career. He spent a short time at the Hamburg General Hospital also at a institute for retarded children, then started private practice. His career did not keep him from exploring his other interests including archaeology, anthropology, occupational diseases (lead poisoning) and the newly emerging field of bacteriology. (Encarta 95)

Koch’s bacteriology studies first accomplished something big in the 1870’s, when he discovered that anthrax, an infectious disease, appeared in mice only after the rods or endospores of Bacillus anthracis was injected into the bloodstream. Koch’s demonstration was a major breakthrough as it was the first time an infectious agent had been linked to a disease beyond a reasonable doubt. This in turn disproved superstition about disease being caused by magic or spirits and proved that they are caused by microorganisms, in this case, bacteria. (Encarta 95)

Koch then showed how one would work with such an organism, to get them from subjects, to grow them in a lab and eventually, how to kill them. Then, he went on to demontrate these things to a German pathologist Julius Friedrich Cohnheim and his associates, one of whom is considered to be the founder of modern immunology, Paul Ehrlich.(Encarta 95)

Born in Dole on December 7, 1822, Pasteur, the son of a tanner, Spent his boyhood in Arbois. At the Ecole Normale in Paris in 1847 he became a doctor in boath physics and chemistry. Later he became interested in souring milk and develpoes a method of decontaminating milk called pasturisation in wich you heat the milk to a high temperature and pressure before bottling.(Infopedia)

Sir Alexander Fleming, who later discovered penicillin, 1920s the British bacteriologist Sir Alexander Fleming, who later discovered penicillin, discovered a substance called lysozyme in tears, sweat plant and animal substances, exc. While it is usefull mainly against harmless bacteria, lysozyme has strong antimicrobial agent. Discovered accidentally in 1928 Its effectiveness agenst disease-causing bacteria was shown in a lab. (Infopedia)

There are several differnt types of bacteria, first split into two goups, Aerchybarteia and Eubateria. Aerchybatcheria Are considered the less primitive and older of the two. They mainly enjoy the more extream enviorments, mudpots, deep sea vents and hot springs. Eubacteria is considered the more evolved and newer of the two. Most bactreia are Eubateria and they cause most of the diseases we are familar with. Below Eubateria are the classifacations of autotrophs and heterotrophs. Autotrophs being the types of bacteria that can make your own food and heterotrophs being te types that must eat to get food. Of the autotrophs there are the photosynthedic autotrophs and the chemosynthedic autotrophs. Photosynthedic autotrophs are plant like in the way that make their food with the energy of sunlight. Chemosynthedic autotrophs, however, make their food with inorganic chemicals. On the side of the heterotrophs are the saprobes who feed off of dead organic life. On either side there are the oblate aerobes and oblate anerobes. The oblate aerobes need oxygen to survive while oblate anerobes are killed by oxygen.

Bacteria are reletively simple cells compared to those of multcellular organisums. Its pretty much just a sack of water with some genedic material. Outside the plasma membrane there is a rigid cell wall that gives the cell structure and maybe a few flagella, a whiplike appendage used for movement. The genedic material is localised in an area called a nuclioid.

You can tell alot about your bacheral type by the properties of the colony. The edges, for example, can be entire (smooth and round), toothed (sharp jagged edges), filimented (looks hairy), lobed (the edge buldges out and folds in at the base) or wavy (like entire but with waves). Also, the colony color can vary from a clearish milky white to a viscuous yellow. Even the colony’s structure, some bulge while others sink in the middle, like a volcano.

Bachteria move by the means of flagella. Flagella are whiplike projections that thrash around to move the cell. Flagella that are on opposit end from eachother are called polar flagella while flagella that are spread arond the cell are called . These types of bachteria that have flagella are called Flagelites which are considered more primative than the Cillates. Cillates move by means of cilla which are like flagella but smaller and more numerous. They move the cell by rippeling in the opposit direction of where they want to go.

Bachteria process foods in a number of ways. The saprobes, for exaple, secreat digestive ensymes out of their bodies and draw the useable chemical into themselves. Photosynthedic autotrophs use the suns energy to make food useing this chemical reaction 6CO2+6H2o ==> C6H12O6+6O2 . This produces the chemicals they need to live. Another type of photosynthedic autotroph uses H2S in their raction rather than H2O. This reaction goes as thus 6CO2+6H2S==>C6H12O6+6S2. There are also bachteria called Methanogens which make methane as thir byproduct which goes CO4+H2==>CH4+2H2O

All through history bacheria have shaped the developement of mankind. Boath helpfully and harmfully. Diseases such as teberculosis and such ran rampant and killed entire villages. Now, as we aproach the twentyfirst century we delude ourselves with thought of safty agenst these invisable agents, however our arrogence is unjustafied. E. Bola and similar diseases still run rampant and old foes have come back in a new for we can’t fight.

Bachteria have also helped mankind throught the ages. The developement of cheese, for exaple, allowed a viable food sorce to be made from milk that would have gone to waste. Bachteria also helps tan hides, where do you suppose our civilisation would be without leather and hides?

Now, as we approch the new melenium, we begin to explore the fronteer of genedic engeneering or the changeing of genes through mechanical means. Using this new technolagy it is possable to do allmost anything. Imagine entire cities built from organic matter, earthquake and fire damage repares itself, any organic waste is injested and converted to energy, lights are replaced with biolumanecent cells and fossil fules become obselete. Truely a utopia.

To grow our colonys we used a beef auger medium which is bacically a bunch of dried, ground beef meat, bones, guts and whatnot. Prepared correctly with water it sets into a sort of meat Jell-o that provide food and water for the colonies. The petri dishes were constructed with a “lip” on one side so the lid would not fit flush, provideing air.

To collet our samples we all dispersed out into the school grounds and took swabs of places with moisened Q-Tips that were carried back in test tubes. Apon returning to class we then stoke the auger in a standered “S” pattern and put the innaculated dishes into the incubator which was set at about 75?. We stored the petri dishes lidside-down as not to accidentally flood the medium

Studphish




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