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#1
12-18-2012
 USMLE Forums Scout Steps History: Not yet Posts: 36 Threads: 9 Thanked 6 Times in 6 Posts Reputation: 16
problem with a mcq of micro,plz help

page 214

a flask innoculated to a density of 3 * 10`3cells/ml
what wil be the density of the culture after 50mins ?
lag period=10 min
generation 20 min

#2
12-18-2012
 USMLE Forums Scout Steps History: Step 1 Only Posts: 88 Threads: 22 Thanked 16 Times in 15 Posts Reputation: 26

lag time=10 min so at this period there is 3*10^3 bacteria.i usually draw a time line...
10(starting point).....30(10+20)......50(30+20)...
12*10^3 is the density of cells at end of 50 mins but you gv and in standard form so 1.2*10^4..
hope you understood.
#3
12-18-2012
 USMLE Forums Scout Steps History: Not yet Posts: 36 Threads: 9 Thanked 6 Times in 6 Posts Reputation: 16

Quote:
 Originally Posted by usmlenj lag time=10 min so at this period there is 3*10^3 bacteria.i usually draw a time line... 10(starting point).....30(10+20)......50(30+20)... u had 3*10^3...................6*10^3..........12*10^3 12*10^3 is the density of cells at end of 50 mins but you gv and in standard form so 1.2*10^4.. hope you understood.
yeah thanx
just one thing i need to clear abt lag time, in the above example we hv to add lag period once at the start right?not after every generation ?

#4
12-18-2012
 USMLE Forums Scout Steps History: Step 1 Only Posts: 88 Threads: 22 Thanked 16 Times in 15 Posts Reputation: 26

Quote:
 Originally Posted by aliawn88 yeah thanx just one thing i need to clear abt lag time, in the above example we hv to add lag period once at the start right?not after every generation ?
yup... lag period tell you the staring point and then you follow the generation time...
 The above post was thanked by: aliawn88 (12-18-2012)

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