Question

J. Uvelle Unuwing data, calculate the original cell density of the culture tested. SHOW ALL WORK. Plate 1 (105): 6421 colonies Plate 2 (106): 639 colonies Plate 3 (107): 68 colonies Plate 4 (108): 7 colonies 4. If you take lul of a 102 dilution and add it to 9.999ml H,O, what is the final DF? Show work. Experimental: Perform the serial dilution as seen below (9.9ml tubes=yellow top, 9.0 ml=blue) 1ml A 1ml A 1 ml A 100ul a 100ml a ZZ 9.0 mL 9.0 mL H2O 9.0 mL H₂O 9.0 ml. H2O Hz0 9.9 ml Н,0 9.9 mL S. marcescens culture DF=___ DF=_ H20 DF=_ DF=_ DF=_ DF= OCD DF=0 - ntable Plate (Y/N)

Answer 1

4. lul. o.ool ml When I add 1 ml in 9ml 4,0; the dilution is 10 es 1/10 When I add olml in 9.9 ml 4.0; the dilution is 102 as 1/100. When I add o.olme in 9.99 ml 4o, the dilution is 10 When I add bool ml in 9.999 ml 4.0, the dilution is 10 as 1/10000. In the given condition, Aulis added of a 102 dilution to 9.999 mL 40 i.e. the total dilution will be previous dilution & dilution due to addition or 1 ul to 9.999 wl no Thus, previous délution is 10-2 and dilution due to addition of hul to 9.999 ml 4.0 is to Therefore, total dilution is 10-2x 10-9 10-6 As Dilution factors & dilution Thus, Dilution factor (Of) - - 108 Hence, the final dilution factor (DF) is 100

Experimental 100ml a bol ml oolmL o.lmL 9.9mL H2O gian qon que quan que 40 40 40 40 40 DE 20 DF 2 10² DF 104 DF - 10 DF = 10" DE 10t DF 2 108