I also forgot to mention something important:
In the 4th week of the experiment (between 6th and 13 of June, 3 of 4 of the right side up plants became root bound.
http://davesgarden.com/guides/terms/go/751/
This basically means that the roots have no more room to grow so they start to build up at the bottom and get tangled and stuff, and this affects their growth. I have a pic :)
The same amount of soil (and same type) was put in each of the bottles (except for the smaller ones- less was put in, but the same amount in the right side up and upside down plants), and since the bottles are clear, you can see some of the root growth. The upside down plants' roots aren't even halfway up the soil thing, which I can use to support GEOTROPISM.
Here is a general definition:
http://www.merriam-webster.com/dictionary/geotropism
Now, when talking about geotropism in plants, i found this a more useful site:
http://www.biology-online.org/3/5_plant_hormones.htm
Anyways, it basically means that plant roots will try to grow as best they can DOWN, and the shoots and stems etc, UP, like a normal plant, even if they are turned upside down.
This is supported by my experiment, because while the roots of the right side up plant have become root bound and run out of space, there is plenty of space that the roots havent used in the upside down bottles. This is because they want to grow downwards like a normal plant, due to its response to gravity.
The actual plant itself has been growing upwards, with it bending back up towards the sky. However, this could also be a result of it growing in the direction of light. (Phototropism)
Btw, tropism means
'the movement of a plant in response to a stimulus (an external force)'
http://www.enotes.com/science-fact-finder/plant-world/what-tropism
So you can kinda get why phototropism and geotropism sound a little alike.
ANYWAY, i will now add more pics, including rootbound-ness!!!!!
I hate it how when you upload an image, it goes to the top of the post :(
wait- does it? watever. i think it does.