Microbiology equation problems Please help and show work 1 A
Microbiology equation problems, Please help and show work!
1) A single bacterial cell and its offspring dividing every 15 minutes will reach a population of 1,000,000 cells in how long?
2) If the generation time for E. coli is 20 minutes and you inoculate a flask with 1 cell, how many cells will there be in the flask 24 hours later? Assume no lag period.
Solution
1)Generation time ,G = Time in minutes or hours (t)/ Number of generations (n) /..................Equation (1)
G= 15 minutes , t=?
From equation 1 , we get n= t /G
x= X * 2n..............................binary fission growth expression equation (2)
where x= number of bacteria at end of time = 1000000
and X=number of bacteria at the beginning of time = 1
From equation 2 , we get n= 3.3 log x/X
substituting the values we get
t/G= 3.3 log (1000000/1)
t/15 = 3.3 *6
t =297 minutes (ans)
2) Generation time(G )= 20 minutes
Initial bacteria (X )= 1
Time (t)= 24 hours = 24*60 minutes
n = t /G
= 24*60 / 20
= 72
Number of generations, n = 3.3 log x/X
72 = 3.3 log x /1
21.8 = log x
x= 10^ 21.8
=6.30* 1021 cells ( ans)

