Daphnia heart rate Practical

Hey
So I've done a practical on investigating the effect of different concentrations of ethanol on heart rate of daphnia magna.
I have results of 5 different concentrations.
Would a statistical test be applied, if yes which one and how?

Thank Youuuuu

First off, what are the statistical tests you know of

standard deviation
t-tests
chi-squared tests

Standard deviation wouldnt be classed into statistical test but yep other two you've mentioned are

Chi square test - its used to see how close are experimental results to the expected results (frequently used in genetics related question )

Student's T-test - is used to compare two sets of data which are normally distributed. ( eg: surface area of leaves in shady and light conditions)

Spearman's correlation coefficient : test the strength of correlation between two variables ( eg correlation between aggression and testosterone levels )

Out of the three, which do you think is suitable?

That's what i am struggling with. I dont have 2 variable's as I have used 5 different concentrations of ethanol rather than two. So would a statistical test be applied or not? I'm not sure how to do it with 5.

Do you think if I was to get expected data for these concentration i'd be able to do the chi-squared test?

Ah but you've got two variables the concentration of ethanol and the heart rate of Daphnia.
The different concentrations of ethanol all are under one indepent variable : concentration of ethanol

Certainly not chi square since we havent got expected results...

oooh I see, so would I carry out the spearman's correlation test? to see the strength between the relationship? As conc. of ethanol increases, the heart rate decreases. so the value would determine the strength of correlation, there fore supporting my hypothesis?

aye yepp

omgggg thank you so muchhhh!!!

Glad to help its tricky and yep ive struggled w/ it it too but once we practice examples for we get an idea

True, your help was appreciated a lot definitely would ask you again if I need anything. Thank you once againnn.

Cheers Let's help each other

oooh I see, so would I carry out the spearman's correlation test? to see the strength between the relationship? As conc. of ethanol increases, the heart rate decreases. so the value would determine the strength of correlation, there fore supporting my hypothesis?