How do Plants Grow?
How do Plants know which way to grow?
If you've ever planted seeds in the ground, perhaps you have wondered just how do
they know which way to grow. How do the roots know to grow down and how
do the stems and leaves know to grow up?
What
You'll Need:
There
are two parts to this experiment. In the first, you'll need a house plant
and a few books. The house plant should not be a vine, Diffenbachia works
great. In the second part, you'll need some pinto beans, a glass, aluminum
foil, paper towels and a record player capable of 78 RPM speeds.
What
to do:
Take
the house plant and lay it on its side leaning against the books. Observe
the position of the stem and leaves over a period of one week.
What's Going On?
Now
Try This:
For
the second part of this experiment, place the pinto beans in a glass of
water and let them soak overnight. Now tear 4 pieces of aluminum foil about
1 foot square. Place a paper towel in the center of each piece of aluminum
foil and moisten each towel. Don't make the towels dripping wet, they should
only be damp. Put four beans in the center of each paper towel and fold
the foil jaround the towel, closing each end. Let the foil and beans stand
for 3 days. Then space the foil pieces on the turntable of the record player
and turn it to 78 RPM. Allow the machine to rotate continuously for 5 days.
After the 5 days are up, turn off the record player and without changing
the position of the foil, open them up and observe the beans.
Now What's Going On?
Copyright © 1997 Kathy A. Miles and
Charles F. Peters II