International A Level Biology / Microbiology
Measuring growth: cell counts and dilution plating
Edexcel International A Level Biology (YBI11), chapter 17: Microbiology, specification point 6.2. Part of the full course.
Read the revision notes · International A Level Biology past papers
Cell counts estimate the number of microorganisms in a culture. A haemocytometer measures cells in a known volume, while dilution plating counts living cells that can form colonies.
More lessons in Microbiology
- Bacteria and viruses compared
- Lytic and latent infections
- The bacterial growth curve
- Calculating exponential growth and the growth rate constant
- Culturing microorganisms with aseptic technique
- Measuring growth: turbidity and mass
- Core practical 13: growth of microorganisms in liquid culture
- How pathogens enter and how the body keeps them out
- Tuberculosis: how Mycobacterium tuberculosis causes disease
- HIV: how the virus infects and leads to AIDS