International A Level Biology / Microbiology

Measuring growth: turbidity and mass revision notes

Edexcel International A Level Biology (YBI11), chapter 17: Microbiology, specification point 6.2. Part of the full course.

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Turbidity estimates the total number of cells from how cloudy a liquid culture is, while dry mass measures its biomass after the water is removed. Knowing what each method measures helps you choose the right way to measure microbial growth.

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