2.2. Haemocytometer
The gridded area of the haemocytometer plate consisted of nine 1×1 mm (1 mm2) squares. These were subdivided into 3 sections: 0.25×0.25 mm (0.0625 mm2), 0.25×0.20 mm (0.05 mm2) and 0.20×0.20 mm (0.04 mm2). The central square was further subdivided into 0.05×0.05 mm (0.0025 mm2) squares. The remaining squares were not used. The raised edges of the haemocytometer plate hold the coverslip 0.1 mm off the marked grid, giving each square a defined volume (https://en.wikipedia.org/wiki/Hemocytometer). Cells in suspensions were deposited into a haemocytometer.
\begin{equation} \mathbf{\text{concentration}}\mathbf{\ of\ yeasts\ in\ original\ mixture=(}\frac{\mathbf{\text{number\ of\ yeasts\ counted}}}{\mathbf{(proportion\ of\ chamber\ counted)(volume\ of\ squares\ counted)}}\mathbf{)(}\frac{\mathbf{\text{volume\ of\ diluted\ sample}}}{\mathbf{\text{volume\ of\ original\ mixture\ in\ sample}}}\mathbf{)}\nonumber \\ \end{equation}