Tutorial 5

Suppose that in the plates above, you have 1500, 750, 400, 55, 16 colonies in each of the plates correspondingly.

1. Calculate CFU/ml if 0.1 ml from the diluents was poured onto each separate plate.2. Calculate CFU/ml if 0.2 ml from the diluents was poured onto each separate plate.3. Calculate CFU/ml if 0.05 ml from the diluents was poured onto each separate plate.

4. Calculate CFU/ml if 1 ml from the diluents was poured onto each separate plate and the amount of bacteria is as follows (ascending order) 4, 32, 430, too many too count, etc.

5. What if 500µl was spread onto the plate?6. What if 100µl was spread onto the plate?7. What if 5 ml was spread onto the plate?

8. Calculate CFU/ml if 0.1 ml from the diluents was poured onto each separate plate and the amount of bacteria is as follows (ascending order) 4, 32, 430, Too many too count, etc.