is the 1st or 2nd one correct...pls explain why You resuspend a single colony of
ID: 146026 • Letter: I
Question
is the 1st or 2nd one correct...pls explain why
You resuspend a single colony of SBW25 (SM) cells in 200 ul of King's B medium and make serial dilutions from this suspension by 1) adding 10 ul of suspension to 990 ul of King's B, 2) adding 10 ul of the first dilution to 990 ul of King's B and 3) adding 10 ul of the second dilution to 990 ul of King's B. You plate 100 ul of the third dilution on a King's B plate, incubate the plate at 28 degrees C for 2 days, and count 78 colonies that grew. What was the density of the original cell suspension in CFU/ml? 7.8 x 108 7.8 x 10 3.9 x 107 1.56 x 10 3.9 x 108Explanation / Answer
Answer - 1.56 X 10^9
10/1000 X 10/1000 X 10/1000 = 1/100 X 1/100 X 1/100
1/10^6
CFU/mL = cfu/ml = (no. of colonies x dilution factor) / volume of culture plate
volume of culture plate = 100ul = 0.1ml
78 X 10^6 / 0.1
78 X 10^7
Initially we take 200ul
So, 78 X 10^7 X 200 = 15600 X 10^7
= 1.56 X 10^9
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.