Help with biology extended essay topic

[Chloe]

Although my teachers generally discourage from a EE in science if you are doing 2 HL (bio and chem), I know that they are the subjects which I am very good at and I actually love studying. I have been debating over my ideas for topic choices over the last couple of days and I would like some help in deciding which topics are more appropriate for EE. I have not quite composed a research qn yet but these are the general ideas.

1. The effect of sunscreen and its ability to decrease the intensity of the radiation - i would perform this experiment on plants not humans obviously for the ethical reasons

2. The rise in acidity of soil due to acid rain and the impact it could have on on the growth of plants

3. How chemicals commonly found in acne products kill and inhibit the growth of bacteria

Thanks for your help!

[AnjaDe]

I think the third one is good! 

In the first one you would probably have issues with background data and you know sunscreen is for humans, and you are using plants, so if the results are reliable and what conclusion can you draw from that and probably you would not be able to show your knowledge in biology. That's just what I think, but I don't have much knowledge in the area.

This second one seem fine, but all the controlled variables you need to consider... You can just adjust the pH and see how it affects the growth of one plant, but then you need to see the acidity of soil in your area and see what plants are growing there. I don't know, I think it's too vague for an EE, maybe if you focus it a little bit.

Third one is a nice experiment, probably with loads of background data that you can use for research and also you can draw clear conclusions from it while also discovering something interesting for you. It's clearly linked to biology and touches upon the syllabus, so you can show your knowledge of the subject.

Those are my first impressions, but again, I didn't work with most of the material you proposed to investigate, so I'm no expert