Experiment suggestion needed (1 Viewer)

[silvermoon]

I have a problem with this dot point:
Identify data sources and perform a first-hand investigation to demonstrate the effect of environment on phenotype
When we went over this in class, our teacher gave us two examples: one was sailors in submarines who dont tan because they arent exposed to sunlight and the other was a study done on japanese identical twins (they were separated at birth and one was sent to america. it was shown that different nutritional patterns led to differences in height).
HOWEVER, neither of these would be realistically classed as 'first-hand' investigations. so my question is, does anyone have a suggestion of what would be an acceptable experiment for this dot point?

 

[xiao1985]

there's this flower i forgot the name... it grows pink in basic soil conditions and blue in acidic conditions... if u r in an agriculture school, you may very well do that 1st hand investigation...

 

[babydoll_]

Hydrangea, xiao

 

[incredible]

A common experiment is with Hydrangeas, testing the effect of pH on petal colour
the Environment is "pH conditions", the phenotype is colour
Grow at least 5 Hydrangea seedlings
Grow in exact conditions (for reliability and were not testing effect of water concentration etc.)
After few weeks before bloomin adjust each pH of ech soil. Add sodium hydroxide in different concentrations for more basic soil. Add Hydrochloric acid (dilute) in different concentrations. Test the pH of these solutions first and of course the pH of the soil
Keep 1 as control!
Analyse the results after a few weeks.
Those with the basic solution should have pink petals. Those with acidic should have blue

 

[malkin86]

I thought that was wrong.. that the colour was due to the minerals rather than the acidity of the soil...

just get some grass seeds or something, grow some in sunlight and some without. The sunlight ones will be green, and the without sunlight ones will be a sickly kind of yellow. to prove that they have the gene for green, you can leave the non-light ones out for a bit and they'll turn green.

 

[silvermoon]

thankyou so much guys - that was a real help! *lotsa hugs to all*

 

[xiao1985]

Hydrangea, xiao

lolz, thx babydoll_ =)

also thx incredible and malkin 86: i think it is due to ph... dont' ask me, i dont' do bio anymore in uni @@

i did skin color i think, so i didn't remmeber that =p

 

[TheKing]

I thought that was wrong.. that the colour was due to the minerals rather than the acidity of the soil...
.

If I am not mistaken, the change in petal colours is due to the presence of Aluminium ions in the soil... the more acidic the more that are free. That is part of the environment, the chemical composition of it. But i don't see why it would matter, acidity is the environmental change that causes this which then changes the flower colour...

And as with the grass seed example, the one I have done in class and in some textbooks is BARLEY SEEDS. One of the plants they use to make beer with. Aanyway, you grow ten in the light and ten in the dark (or more if you want) and you should see that because the environment was void of light, the gene for chlorophyll was not switched on and so many more albino plants were present in the dark sample.