alqga

Sorry, but I think that to do a correlation you don't neccesarily need replicates. If for example you want to know if there is a correlation between temperature in summer and development of algal blooms you don' t have replicates and still you will be able to do it.  In any case, he didn't say nothing about replicates, so we don' t know about the set up. I agree he can plot the values on a graph, but additionally I think he can perform a correlation to see the strenght of the association. But to see if the treatment had an effect he does need to perform a test.

Either parametric or non-parametric, I think I know the difference. Parametric tests such anova when you have normal and homocedastic data, non parametric, such as anova on ranks (kruskal-wallis) when any of those test fail, am I wrong?

Ok!

Then, if what you want to see it`s if your protein´s increase (or decrase, whatever) is time-dependant, then I think you can use a correlation. But to see whether your treatment had an effect you should compare treated vs control with an anova. Did you only use one concentration of your chemical?The same concentration during the whole time course?

I am not an expert on statistics but I think that the test depends on what do you want to know. I mean, correlations usually are used when you want to find associations between two (or more) variables (let´s say, phosphorus concentration and growth of algae, for example).

Do you want to know if there are differences between your treatments? If that is the case, you can use a t-student (if you want to compare only two groups, lets say treated vs  control) or better a one way anova.  But, as I said, it depends on what is your aim and on the set up of your experiment. If you can provide more information, maybe I can write a more specific example on what test to use and why!

Thanks for answering! So it means that a very low 260/230 ratio won't affect my qPCR results?

The thing is that I have to compare gene expression among tissues, that's what i am a bit worried about such differences. Anyway I have the reference gene so I guess that if there is something wrong with the samples I will be able to see it in that qPCR...

Hi!

You are using the right formula but your C2 is not 2.5x10^5 (thats the amount of cells per well). Your C2 is the number of cells per well divided by the volume of media in your well (2ml). This is, your C2 is 1.25X10^5 cells/ml.

What I usually do is to calculate the total volume used for seed. This is, if you want 2ml X6 wells, you need 12ml, so let´s calculate if we had 7 wells, this is 14ml. Now your equation stays like this:

(1.5 X 10^6) V1 = (1.25 X 10^5) (14ml)

V1= 1.16 ml

14 ml -1.16= 12.833 (volume of media to dilute)