Microlec Day 3 Discussion. Basic laboratory equipments 1. Autoclave - this is an equipment that uses moist heat for sterilization- steamin - it is with pressure It is done or used for 15 minutes at a temperature of 12 degrees celsius at 15 pounds per square inch. - This is also used for sterilizing the culture media which is agar. Process Sterilization of erlenmeyer flask and beakers - insert a cotton swab then wrap it with a piece of paper which is cut in the shape of a circle. - then tie with a thread to put it in place. Sterilization of pipettes - cover with paper material - the cap or the paper should be longitudinal - this is done after removing from the autoclave - allow to cool down before dispensing the culture media which is agar - prepare bunsen burner - and do not allow other to solidify - remove paper or cotton once other cools down to 45 degrees celsius - heat the mouth of the erlenmeyer flask before pouring on petri dishAdditional information: if it is done in a plate it is called plate media, if it is done with tubes it is test tubes. Plate media sterilization is done before disposing Test tubes - Dispensing is done before sterilization. - After Meltingthe agar we Immediately dispense in test tubes, each test tube will be cotton plugged. test tubes will be placed in a beaker and will be covered. - Beaker will then be placed inside the autoclave Preservation Place the organism in the fridge if it will not be used yet. 2 . Hot air oven or sterilizer - this is based on the principle of dry heat temperature is about 180 degrees celsius after sterilizing and autoclaved with then transfer sterile materials in the hot air oven so there will be a double sterilization process from autoclave to hot air oven 3. Refrigerator most necessary laboratory equipment used for storage of culture media for agar. 4. Incubator This laboratory equipment is responsible for supplying the temperature requirement of bacterias in order for them to grow. the the optimum temperature is about 37 degrees celsius it requires for about 24 hours to allow an organism to grow The incubation period lasts for about 24 to 48 hours. Additional information: biochemical test is done to further observe the reaction of microorganisms to culture media, culturing lasts for about 5 days to 1 week. 5. Water bath - A water bath is a laboratory equipment that is used to incubate samples at a constant temperature over a long period of time. Water bath is a preferred heat source for heating flammable chemicals instead of an open flame to prevent ignition. 6. Colony counter This laboratory equipment is used in order to count the colonies grown in a culture media. 7. Incinerator This laboratory equipment is responsible for heating the end of inoculating wires in order to kill organisms that are present. this uses electricity An incinerator that kills bacteria is called bacticenerator. 8. Centrifuge separates sediment from the liquid. 9. Pipettes - Used for measuring small volumes of liquids. 10. Volumetric flask - Give accurate volume measurement has specific capacity has only one calibrated mark Note: anything measuring should be exact and not estimated. Bacterial morphology bacterias have inner and outer structures just like any other organisms. External structures. Glycocalyx outermost structure composed of polysaccharide which is carbohydrate and polypeptide which is protein or both. can be called as capsule when strongly attached to the cell wall can also be called slime layer if it is loosely attached to the cell wall its presence indicates virulence ( strength) or degree of pathogenesis It is considered as antigenic because it can stimulate immune response. they provide protection for dehydration also called as sugarcoat Additional information: Microorganisms in nature are antigenic because they stimulate production of antibodies once they enter our body. Flagella long filamentous appendages provide the capacity to used for motions has they are locomotory structures 4 Arrangements of flagella monotrichous (having one flagellum) amphitrichous (single flagellum at both ends) lophotrichous (numerous flagella as a tuft),Two or more flagella at one pole. and peritrichous (flagella distributed all over the cells). - Not all bacteria has a flagellum flagellums are only present in organisms capable of motion - In eukaryotes- flagella causes angulate or wavelike motion in prokaryotes- flagella causes rotation seen as a moving clockwise or counterclockwise Axial filament anchored at one end of the organism such as spirochetes seen in spiral organism - Produces a corkscrew motion example is treponema pallidum the bacteria that causes syphilis Fimbriae hair like appendages used for attachment consists of protein mainly pilin. when this is absent colonization cannot happen, therefore, there is no disease Pili - longer than fimbriae Usually, there may only be one or two pili major organism This joins bacterial cells in preparation for the transfer of dna from one cell to another- this is its most important function. healy are sometimes called sex pili Internal structures Nucleoid contains genetic material which is the dna does not contain a nucleoplasm or cell membrane Mesosome functions for cell division involved in the secretion of substances for the bacterium Ribosomes site of protein synthesis Some antibiotics for treatment targets ribosomes to destroy and kill the organism that causes pathogenic diseases to hosts, especially humans. Granules or inclusion body - Storage of food and energy Endospores - Spores encountered in bacterias makes an organism resistant to destructive factors such as heating drying and chemical agents. -John Darrel Ramillano BSN1-D - wabyu:3
