Workbook in Microbiology 7e

15. Record your observations of growth or no growth in the chart.

Streptomycin

Concentration

Plates (No. of Colonies*)

Broths (Turbidity + or -)

100 ^g/ml

250 ^g/ml

None (control)

*If the number of colonies is greater than 300, record as TNTC (too numerous to count).

*If the number of colonies is greater than 300, record as TNTC (too numerous to count).

16. From each agar plate on which you see bacterial growth, suspend a few colonies in a tube of sterile water. Streak a loopful of the suspension onto the correct section of the 3 freshly prepared agar plates labeled "agar." For example, colonies growing on the plate that contained 100 |lg of streptomycin/ml, will be streaked onto the three sectors labeled "SM 100" on each plate.

17. Streak a loopful from each of the three flasks onto the corresponding sectors of the plates labeled "broth."

18. Seal all plates with Parafilm and incubate at 35°C.

19. Examine the plates at the next session and record your results in the chart.

Growth (+ or -)

Agar

Broth

Streptomycin Concentration

SM 100

SM 250

No SM

SM 100

SM 250

No SM

100 ^g/ml

250 ^g/ml

None

State your interpretation of these results.

State your interpretation of these results.

Do you have any colonies on your plates that arose in the presence of streptomycin but do not grow when subcultured to media without streptomycin? What would be the explanation for this phenomenon?

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Bacterial Vaginosis Facts

Bacterial Vaginosis Facts

This fact sheet is designed to provide you with information on Bacterial Vaginosis. Bacterial vaginosis is an abnormal vaginal condition that is characterized by vaginal discharge and results from an overgrowth of atypical bacteria in the vagina.

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