the effect of pHlevel on growth of duckweed?
375393
Duckweed growth best between pH 4.5-7.5 , it can tolerate a larger range, but with a pH larger than 10 it will not be able to grow properly
760170
The plant idea of a previous answer is great, that is, assess the effect of a lack of water, sunlight, soil, air, etc. on plants.\n\nOr what about feeding a plant different liquids (tap water, rain water, salt water, coke, kool aid, etc.) and assess the different affects.\n\nOr "put aluminum/steel cans in different liquids (tap water, rain water, salt water, coke, kool aid, etc.) to assess their effect on oxidation (rusting)"\n\nThe affect of the gender/age/race of the interviewer on survey responses.\n\nOr what about the effect of using different candies/sodas on the old diet coke/mentos fountain.?\n\nOr, depending on where you're located, the affect of elevation of an automobile's gas mileage.\n\nFinally, you could look at the affect of sleep deprivation on an individual.\n\nGood luck
502267
Transpiration and concentration gradients
813056
During  a recent experiment our finding with red, green, blue, yellow and clear lights were as follows:\n\nOur results show that the red group grew the most in height, and the yellow and green groups exhibited similar amounts of growth. The blue group grew the least of the colored groups, but the clear and control groups grew the least of all the groups.
283817
It has a and b.  C is only present in certain types of algae.\n\nNatural light generally works the best but if you don't have enough, try using a grow light.
675640
In one seminar I attended, on plants containing pharmaceuticals, the speaker commented that they may have first arisen as an accidental byproduct of the plant's own metabolism.  They lack an excretory system, so they can just shed odd compounds into old leaves, bark, etc, to get them out of living cells.\n\nIf the plant is then under attack by an insect (or other small animal, eg a slug or snail) that tiny herbivore may spend much of its life cycle feeding on a certain plant.  Thus, that animal gets a huge dose of whatever odd compounds the plant has made.\n\nIf these compounds slow down that animal, by killing it, or just confusing it so it drops off the plant, this characteristic will confer a selective advantage to that plant.  It may lead to more of the toxic compound being made, not less.\n\nHe said that these effects are less likely to be useful in deterring larger animals, for whom a certain plant species might form a very small % of a browsing (or gathering) diet.
385167
Some plants thrive in a low pH-leveled soil (such as rhododendrons and azaleas), and other kinds of plants thrive in a high pH-leveled soil.  Give the plants the opposite of what they need, and they will mostly likely die.
734392
Depends on the plant. Some plants grow faster than others.
69117
this depends on the plant...different plants have VERY different requirements!
185814
what the hell is 'the hydro'? HYDRO IS NOT A TYPE OF WEED, it just means it was grown in water, i've bought hydro that was completely poop before. besides, growing hydroponically is in no way easy at all. anyway, if you want potency, a couple strains are; white widow, northern lights, nyc diesel, ice, god bud, neville's haze, ak47. the only real 'easy' strain is lowryder. otherwise try to find a strain that doesn't have a long flowering period, these should be easier to work with.
927156
drift wood will lower pH as it releases tannic acid as it soaks.\n\npeat moss will have the same effect , but will release humic acids.
222680
temp 30-34 deg C\nadequate Nitrogen & Phosphorus\nwell watered but well drained\nNot too Humid\nC02 level 1000ppm
1168459
Invite a bunch of kids into your hottub, they should raise the PH level! jk\n\n"sodium bicarbonate or baking soda raises the kH and pH as mentioned by Goldy. As mentioned, at low pH, the good bugs do not thrive well and the filtration suffers. A pH level between 7.0 to 8.0 would be good. pH should not be raised suddenly to prevent pH shock. Therefore baking soda should be added little by little over a few days. A dosage of 25-50g per 1000L per day until the desired pH is achieved should be OK. As it is easily soluble in water, dissolve it in a pail of water and distribute evenly over the pond. It may need to be replenished after sometime depending on the stocking level as it is being used up by the filter. A more permanent solution of maintaining alkaline pH is to use shells (oyster, cockle) as pH buffers. They act by releasing carbonates slowly. \nIf the ammonia level in the pond is very low, there shouldn't be much danger in raising the pH slightly. As for the location of the UV, I would prefer to place it at the last stage of filtration, that is after the biomedia, and in a separate chamber."
571423
I typed "9th grade biology experiment" into Yahoo Search and found some experiments.  Here's one of them: http://www.wested.org/werc/earthsystems/biology/fertilizerfrenzy.html\n\nYou may want to tweak the query to find better results.
239684
It sounds like the kind of thing that would reduce the growth of plants.  But maybe there would be more helpful answers in a section other than "Comics and Animation".
395646
Depends on the plant.  Some plants, like kelp or Utricularia thrive when totally immersed.  Others cannot transpire properly unless their leaves are exposed to air, and will 'drown' in water.
92173
You should find the answer you seek here...\nhttp://www.biology.lsa.umich.edu/~gwk/teaching/limno/lab/onlinemanual/chlorophyll.html\nhere...\nhttp://www.steve.gb.com/science/natural_selection.html\nhere...\nhttp://plankt.oxfordjournals.org/cgi/content/abstract/24/11/1221\nor here...\nhttp://en.wikipedia.org/wiki/Phaeophytin