Generation Time... HELP?!

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baffledbiologist
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Generation Time... HELP?!

Post by baffledbiologist » Sun Oct 16, 2011 12:04 am

I am new to this forum but I need help! I am currently dong a microbiology report at university. We done an experiment on two cultures (L and M) measuring the growth using a spectrophotometer set at OD600 at set time intervals (every 30mins, 0-150). We then had to find and plot the natural log, these were my results (obviously not on a graph):

Time Culture L lnCulture L Culture M lnCulture M
0 0.065 -2.733368009 0.026 -3.649658741
30 0.167 -1.789761467 0.043 -3.146555163
60 0.335 -1.093624747 0.044 -3.123565645
90 0.508 -0.677273831 0.064 -2.748872196
120 0.942 -0.059750004 0.082 -2.501036032
150 1.322 0.279145741 0.117 -2.145581344

We then had to find the cells ml^-1, which was easy enough, then had to find the specific growth rate and generation time of each culture using the following equations:

μ = (lnODt2 – lnODt1) / (t2 – t1) and g = ln2 / μ

I think I managed to get the growth rate (μL = 0.021h^-1 and μM = 0.010h^-1) but I can't seem to figure out how to get the generation time?! I have been looking at it for so long and have tried so many different things that I've completely confused myself :( (I ended up with 33 and 69 hours or something ridiculous)...

Sorry for rambling... ANY help would be much appreciated, I'm so annoyed and confused! :?

Thanks a lot.

baffledbiologist
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Post by baffledbiologist » Sun Oct 16, 2011 12:07 am

Oops! My results aren't very clear. Sorry, I'm not sure how to sort it so I hope someone can decifer them and solve my issues!

baffledbiologist
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Post by baffledbiologist » Sun Oct 16, 2011 12:34 am

Okay sorry again! I have managed it! Not sure how I delete this though, technology is not my forte.

daniel.kurz
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Post by daniel.kurz » Fri Oct 28, 2011 5:45 am

Sounds like from reading this that you missed a decimal because your work is right. I got a time of 33 minutes and 69 minutes which is reasonable.

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