What different agar plates are for скачать в хорошем качестве

What different agar plates are for

Agar plates are an essential tool in the microbiologists tool kit. They are a convenient, effective and practical way to grow microbes. Even better they can be adjusted to suit a range of different applications. At its most basic an agar plate is a petri dish with a 2 to 10 percent agar solution in it. This is not much good for growing anything but is a good substrate to start from. From this basic ‘recipe’ other things are added or subtracted. The most basic change is to add a nutrient solution. This will feed the bacteria. The most basic nutrient solution is tryptic soy agar. There are more compete solutions such as luria broth. Another example is chocolate agar broth. This is a solution that uses real blood. This includes factors that support the growth of certain bacteria. The use of this plate lets you grow certain bacteria over others for diagnostic or production purposes. There are further refinements to chocolate o blood agar. One is Thayer – Martin agar which is used to diagnose gonorrhoea. Another kind of agar plate used is filled MacConkey agar. This selects for only gram negative bacteria. Another means of diagnosing infections and assessing the best antibiotics to use. MacConkey agar is not the only gram negative option although XLD is not used for blood or swaps. Instead it is for stool samples. This is especially useful for GI tract infections and problems. Bacteria are not the only thing grown on an agar plate. Sabouraud agar is sued to grow fungi. You need a unique or at least different substrate addition for fungi as they are fastidious. All of these diverse uses and powerful function would normally come at either great cost or effort. The truth is gar plates are surprisingly easy to prepare and use. While it is true that some care and attention is required to make agar plates it is no more than that required to culture the bacteria in the first place. This means it is more or less the same effort. The volume made for most basic agar recipes is often enough to make between 25 and 50 plates for each batch. These need to be stored and storage is both the easiest and hardest thing. Easy in that all you need is a fridge. Hard in that one small mistake can ruin everything. That mistake is storing the petri plate on its bottom. Petri plates should be stored upside down to avoid moisture condensing and falling on the agar. This prevents contamination during storage. Growing the cultured microorganism is going to vary wildly between species and purposes. That is fungi, viruses and bacteria need different conditions. Even among the same broad group they need different temperatures and times. Once you have your petri plate cultured the final issue remains. Disposal. You just spent time and effort growing these microbes but you need to dispose of them responsibly.