KROK 1 2011 – Question 4 · KROK (Medicine) · Microbiology, Virology, and Immunology
Sanitary bacteriological research on water by the membrane filter method revealed two red colonies on a membrane filter (Endo agar) through which 500 ml of analyzed water were passed. Calculate the coli index and coli titer of the analyzed water:
- A. 250 and 4
- B. 4 and 250
- C. 250 and 2
- D. 500 and 2
- E. 2 and 500
Hint
Convert the colony count to one litre to get the coli index, then work out what volume of water on average holds a single coliform bacterium for the titer.
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