Comment on Prove your humanity.
Little_mouse@lemmy.ca 1 day agoThe standard way to streak a plate involves creating a resevoir of the sample you are studying, then using a sterile tool to streak through that at a steep angle. Then you streak through the first streak with another sterile tool, and so on and so forth.
As you streak through lines, the amount of bacteria pulled along is reduced until you are able to isolate individual colonies.
icelimit@lemmy.ml 1 day ago
Til! Thanks!
Sterile_Technique@lemmy.world 23 hours ago
Visual breakdown for anyone interested:
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beeng@discuss.tchncs.de 23 hours ago
Nice username
Sterile_Technique@lemmy.world 21 hours ago
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icelimit@lemmy.ml 22 hours ago
1 through to the end are all made with new, sterile… sticks?
Look ma, I’m a biochemist now!
Sterile_Technique@lemmy.world 21 hours ago
Pretty much. It’s like a little wire loop - sterilize it with a bunsen burner, let it cool, then take a swab from your source specimen and drag it into your agar for that section 1. Sterilize it again with the burner, cool, then drag through the last couple lines of 1 to get region 2. Repeat for 3 and again for 4. The sample size of individual microbes gets exponentially fewer each time - done correctly and region 4 is dotted with individual cells, which you leave alone for a while to incubate, then come back and start making your observations like how it’s interacting with the agar, what color, texture etc; smear it onto a microscope slide, see how it responds to different stains, it’s shape, it’s arrangement… then start checking all those findings against known properties of different microbes until you find a match.