Common Microorganisms Essay examples -- essays research papers

INTRODUCTIONMicroorganisms such as bacteria, fungus, mold, and yeast are present and common in almost every environs on earth. The norm everyy microscopic organisms freighter easily be seen exploitation differing types of agar, which creates an ideal environment for the organisms to form colonies, which are groups of hundreds of organisms that drive out be seen with the crude eye. In order to see individual microorganisms, it is necessary to use the effusion of a high-powered microscope.These techniques of microbiology are used in the following quin try outs. The first experiment used Trypticase Soy Nutrient agar-agar (TSA), which can grow a wide variety of organisms and contains casein and soybean repast and a minute NaCl, to study the effectiveness of alcohol as a skin antiseptic. The second experiment tested the effectiveness of different kinds of mouthwashes as antiseptics using TSA as well. Experiment good turn three explored the normal mankind flora existing on skin and in nasal cavities, and deuce types of agar were used, including TSA and Mannitol Salt nutrient agar, which contains manitol sugar, phenol red, and 7.5% NaCl. Mannitol Salt Agar tests for the presence of staphylococci bacteria that can survive in the sodium chloride that inhibits the growth of most other bacteria. Some forms of staph bacteria crop mannitol and produce a yellow color around the colonies, which can easily be seen against the red background. The fourth experiment studied the number of bacteria in a diluted sample of uncooked hamburger meat using nutrient agar and a Quebec numberer to count the colonies. The final experiment involved the growth of yeast cells under aerobiotic and anaerobic conditions. MATERIALS - Trypticase Soy Nutrient Agar-Mannitol Salt Agar-Sterile alcohol swab-Listerine mouthwash-Tubes of nutrient agar- cut hamburger meat -Quebec colonisation counter-Apple juice-anaerobic yeast culture-Hemacytometer-IodineMETHODSExperiment 1. Effectiveness of alcohol as an antiseptic1) All experiments must be done in a sterile environment Lysol can be used to sterilize the a... ...ide had a lot of large tan colonies and dense, small colonies. The Listerine side seemed to destroy all most all of these small colonies, but the larger colonies were actually more(prenominal) numerous. The other mouth washes used were saltiness water rinse and Scope. The salt water did almost no damage to the bacteria, and the Scope killed the most. In experiment three, at that place were a lot of different kinds of organisms persent on the agar. On the photographic plate that contained nasal micro-organisms, large yellow colonies appeared on the Mannitol Salt Agar, indicating staphylococci aureus. On the TSA side, small creamy white colonies were also present. These could possibly be yeast. On the plate that contained the skin swab, there was a large do of large, fuzzy white and black growth, which is mold. at that place was a single light-orange c olony on the TSA side, possibly a growth of Flavobacterium.In the fourth experiment, there were a number of different kinds of colonies on the EMB plate with the meat swab. There were black dots, which indicate the presence of E-coli, pink dots, which indicate lactose-fermenters, and a a few(prenominal) white and gray colonies.