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You can put any media in a GasPak or other anaerobic system depending the type of anaerobic growth you are looking for. Sometimes blood is simply added to media to meet nutritional requirements of an organism. I use Columbia Blood agar often as a general purpose anaerobic medium. In a collection of 100+ obligate anaerobes I am working with, around half grow ...


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Blood agar is prepared by heating the blood so that there will be lysis of RBC. Blood agar is mostly used to grow pathogenic organisms such as Haemophilus influenzae and Neisseria gonorrhoeae which cannot grow on other media.Neisseria gonorrhoeae can grow in the absence of oxygen. Haemophilus influenzae which is a facultative anaerobe also can carry out ...


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Rinsing the surface will make the micro organism growth static on the surface i.e it removes the micro organisms from the surface,but it is only for time being.But it is not effective in killing the micro organism.Mostly in labs,70% Alchohol is used to disinfect the surface.It is more effective in killing the organism.


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There absolutly is selection involved. First, you create a selective environment to culture a subset of environmental organisms (yeasts). Then, by infusing fresh media (flour/water) into the cultures each day, you are essentially passaging a live culture or organisms. It's not rational selection, like that practiced by plant breeders, since you aren't hand ...


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That is not Darwinian selection, because you are not selecting anything. As you mention yourself, it doesn't matter which half you discard and which half you keep. In fact, you can keep the entire thing. Discarding just makes it more practical. If all conditions are fine, yeast will grow exponentially, meaning your amount of yeast will double every 2 hours ...


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Yes, continually diluting the mix like this encourages the organisms (bacteria, yeasts, fungi) to have more constant conditions (maximum nutrients, fewer waste products) and be in log phase growth. The mix selects for particular faster-growing organisms. if you did not dilute, the nutrient levels would change (lower) and waste products accumulate much faster....


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Dental damage is mainly caused by the demineralization of the tooth enamel. Demineralization can happen due to a low pH caused either by acidic food/drinks like fruits or carbonated beverages or by bacteria producing acid while breaking down sugars. Measurements (1, 2) have shown that food intake changes the pH (increasing or decreasing, depending on the ...


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Minimum infective dose is the minimum number of infectious particles that causes infection/illness in 50% of those given that dose. Practically this is only really measurable in a controlled laboratory setting, but one can estimate it for real world circumstances as well. It isn't easy to know how exactly the probability will vary around the MID - there ...


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If database and literature searches fail, you can plug the GenBank accession numbers for your genomes into the CARD Resistance Gene Identifier. It takes either protein or nucleotide sequences, though nucleotide seqs. undergo ORF calling first. For example, plugging in NZ_CP009072.1 for E. coli ATCC 25922 gives 7 perfect hits to known antibiotic resistance ...


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