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Biology help ??

Help , I’m currently on the topic of population sizes and using dilution series’ by using yeast culture ect ect and I’ve been given the question asking for an example calculation for working out the size of a microbe population from a sample ? I have no idea , I know how to use a haemocytometer but that’s a different question , please help thanks

Reply 1

helena630

Totally okay ahah thank you anyways

Reply 2

flaurie

Volunteer Team

moved to the Biology, biochemistry and other life sciences forum :smile:

Reply 3

helena630

Original post by laurawatt

moved to the Biology, biochemistry and other life sciences forum :smile:

Thank you

Reply 4

atlanticblue26

Original post by helena630

There was actually a question on that in this year's A-Level Biology (just finished Year 13 doing chemistry, biology and maths). Okay so I assume this sample was diluted for ease of counting. I'll make some numbers up to show you. Let's say you counted 7 microbes in a 10ml diluted sample. But that's after a serial dilution by say a factor of 100, so the original solution would be more concentrated (would have 7 x 100 = 700 microbes per 10ml). If the whole population of microbes was put into 200ml of water originally, the population would have been 14000 microbes (700 x 20) where the 20 is 200/10 to scale up the sample.
I'm not sure if I got the gist of what the question was asking but feel free to send a picture of it or drop me a message with more questions!