Re: how can i prove the environmental effects on the cell membrane?

Dear Amy,

It is indeed a bit late to give you an answer, especially since I'm not 
quite sure what you want to show. To show anything in any detail, you 
would need some serious lab equipment, I'm afraid.

I can understand your question in two ways: either you mean the 
environment in a broad sense, or you mean a negative change in the 
environment, leading to a negative change in the cell membrane, by which, 
I take it, you mean the plasma membrane. Or is it the totality of the 
membranes?

You say that you could have access to a lab. Could you get some help in 
running acrylamide gels here? With a technique called SDS-PAGE, you can 
track the proteins in the membranes. What's in a membrane? Proteins, 
lipids and other organic compounds. To show what's going on, you would 
need to first separate the membranes from the soluble material (often by 
more or less complex centrifugations, depending on how crude you can 
accept the membrane sample to be). Then you need to analyse what's in this 
sample. Any change brought about is probably a subtle one, such as the 
presence of one protein being boosted. I would have to know what you have 
in your lab in order to give any useable advice.

If you can't do anything of this, you have to rely on easily measured 
changes. But from there to show that the change is truly related to the 
membranes, it will be difficult. 

You could check pH-change. Grow some yeast in the presence of different 
compounds and track the pH change over time. The acidifying capacity is 
due to proteins in the plasma membrane.

You could do a simple chromatography of "small" coloured compounds. Grow 
some plants from seeds under different light conditions. Crush the 
material and add both a water-based buffer and a non-miscible organic 
solvent. Gather the organic phase and concentrate by evaporation (BTW, 
don't use ethers if you do this). Take a strip of thick and dense paper 
and add some of your sample at the bottom of the strip. Dip the bottom of 
the strip into some solvent, like ethyl acetate or acetone, maybe mixed 
with some water. See blobs separate along the strip as chlorophyll and 
other coloured compounds migrate at different speeds. Try heating the 
strip over a flame, so that you char any otherwise invisible compounds, 
oxidise others, but don't burn the paper! :-) You could ask your teacher 
for some TLC-plates (Thin Layer Chromatography); they shouldn't be too 
hard to get hold of. There are reagents he could get hold of as well to 
further "develop" the strips (ninhydrin for instance).

I hope this gives you an idea of what you can and - alas! - cannot do for 
you project. What ever you do: have fun! Science is a legitimate way of 
keeping that inner child alive.

Greetings,

Erik von Stedingk