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Biology (podweed) extended essay help

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I need urgent help with my extended essay. I haven't started with my lab and school is soon about to start.

I have been talking to my supervisor and she said that I could take pondweed and put it in 5 different buckets with different PH values.

Does anyone know how pondweed reacts and whether there will be a difference in the growth after 3 weeks? Do I need somethinig special or is it just regular water that will make it grow?

I am planning to take before and after pictures and see if the difference is visual. Furthermore I'm going to weigh the pondweed and pray that a difference in weight will appear.

Sorry if this is confusing but if you understand I'd be super grateful for advice.

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Here isn't the right place to find out how pondweed grows, for that I suggest my best friend Google. However, if you can Google the answer to your original question (which I'm interpreting as, what pH does pondweed grow best in), then you probably should change your question.

Another thing is, you should account for variation. What if the pondweed in bucket 1 grew really large, not due to different pH values from other buckets but from something else? So you should do multiple trials with each different test. And the testing must be done at the same time because pondweed I'm assuming, grows also according to weather. So if you start growing them in August and in December, you're going to have vastly different results. And even then, if you place one bucket in an area where the sun doesn't shine then the results will be different yet again.

And honestly, don't worry if there isn't a difference in weight. When I did my chemistry EE absolutely NOTHING changed. The minute amount of change that I did find were attributed to human and equipment error. It doesn't matter what the end result is, you just have to be able to talk about it. Write about what pondweed is, why you chose it, what its natural environment is and what type of pH its natural environment is. Write about why you think there should be a plausible difference in growth in different pH. And if it really didn't work, write about what went wrong. Point out all your mistakes, and what you could've done better.

Also, I think your topic question might be a bit too obvious. It is a commonly taught knowledge that plants have a set pH in which they function in. Too low and they die, too high and they die. What is it about pondweed that makes you think it won't die? Although, if there isn't a difference in weight, then that's even more interesting actually because that might mean pondweed is immune to pH changes, so it contains a very strong natural buffer in itself (depending on the variation of pH you're subjecting them to). So if there isn't a change in weight, then it's even more, not less, interesting. That would be a more interesting topic question then, if that is the result you get.

Remember, IB isn't looking for right or wrong answers. They are looking for thinking, especially in Scientific EE's. Research everything you are going to do, and show the research. Show your steps. And if you're wrong, show them that you know that you're wrong, and you know where you went wrong. Or just write an educated guess on what happened.

If you have any questions, feel free to ask me. Although I don't know how likely I'll answer, seeing as I don't monitor my Twitter nor my email...

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