You count 30 spores in the hemocytometer in the 02 mm x 02 m

You count 30 spores in the hemocytometer in the 0.2 mm x 0.2 mm x 0.1 mm volume. What is the concentration of the spore culture?

3 x 106 cells/ml

7.5 x 106 cells/ml

1 x 107 cells/ml

1 x 106 cells/ml

7.5 x 107 cells/ml

Solution

count 30 spores in the hemocytometer in the 0.2 mm x 0.2 mm x 0.1 mm volume. What is the concentration of the spore culture?

v = 0.2mm x 0.2mm x 0.1mm = 0.00625mm³ = 0.004 ul (where ul is microliters).

(30 /0.004 ul )= 7500

there are 30 spores in 0.00625ul

1ml = 1000 microliter

(30 cells x 1000ul) / 0.004ul = X

X =7500000=7.5 x10^6 cells/ml

7.5 x 10⁶ =7,500,000.cells/ml ---answer