Bio plz plz plz HELP!!! 10 points 4 Best Answer!?

Question

I'm doing a biology project as part of my A2 course...

I'm looking at the relationship between Leaf length & width and Light Intensity. I found that length and width of leaves are greater when light intensity is less (Leaves found in the shade).

I'm doing a Spearman's rank Coefficient of correlation

I know i have to do leaf length and width in a different table, but what about sun intensity as i have got readings for light intensity (in LUX)

Answer 1

Hi ShaM,

Since the key observation is how dimensions of a leaf relate to light intensity, your tables/plots must include light intensity obviously. So the question really is how (or IF) to include both width and length in the table/plot.

What I would do is separately evaluate the correlation between (a) leaf length and light intensity and (b) leaf width and light intensity. Here are some possible observations you might make:

(1) (a) and (b) are very similar - Then you can collapse the correlations together into "leaf dimensions" vs. light intensity

(2) Only (a) or (b) correlates with intensity - Then only plot the one that does and state that the other doesn't correlate

(3) (a) and (b) show different correlations - This would be really interesting because it would show that leaves manipulate their width and length differently with light intensity. I would then state it as such and plot Light Intensity as the x-axis and Width and Length both on the y-axis

Beware that some of your results could simply be a function of a particular plant or the leaf geometry of a particular plant species. So you may want to test your hypothesis against another species/plant. It will give your study more credibility.

BTW, you asked for a further clarification on your other question that I answered yesterday. But I couldn't respond because you closed the question and your profile doesn't allow me to email you. So let me answer it here as well :-) You wrote:

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Ok so... i just have to give background info? what does that word *rationale* mean lol... its scaring me!

The teacher says i gotta explain why i wana do this experiment?

i jus wana do it coz i GOTA do it lol.. ahh so longg.. thanks for all your help so much guys, its really helpin!

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I totally understand your "GOTTA DO IT" rationale, lolz. It will get you the "cuteness" points but not the "academic" points :-) So here is what I would say (feel free to tweak it):

"The increase in green house gases in the atmosphere is expected to have a profound impact on the biological ecosystem on earth, particularly on the flora. Global warming is not only creating a warmer environment for the plants but also affecting the cloud cover that reflects nearly 50% of sunlight and potentially altering the intensity of light reaching earth's surface.

Hence it is of prime important to study and understand the impact of this phenomenon on plants. Plants interact with sunlight primarily through their leaves via multiple mechanisms such as photosynthesis, water evaporation and CO2 control. So I have chosen to study the correlation between incident light intensity and foliate dimensions in an attempt to understand what impact it may have on plant life cycle in the future"

That should provide a sufficient ration of rational rationale for today :-) BTW, I'm quite impressed with your 59% Best Answers record and Level 4 status - most centered around sciences

Answer 2

possibly less light will mean less energy for growth so the elements must act accordingly in some plants feed leaves  more of the energy threw branches and twigs in regards to there being more moisture in the imediate enviroments. the taller trees raising above the rain forrest canopy may have smaller leaves than the lower canopy trees and plants being in the shaded areas which may have longer wider  much larger leaves they suck up the water faster than higher trees