Before you try the experiments included in this section, we recommend
that you take a look through this introduction, to find out why plants
are so cool!
to Use the Experiments on this Site
The experiments on this site are adapted by NSCORT scientists from
the outreach work they to teachers in the "Plants, Gravity &
Space" Special topics course. The experiments are provided for students
of grades 6-12; some activities students can try at home, while others
require teacher supervision.
The Importance of Plants for Space
NASAs goal is to explore the solar system and to enrich our lives
here on Earth.
The success of long-term space missions depends upon the ability of the
human inhabitants to live and thrive off the land and to adapt to the
new conditions in which they find themselves. In order for this to happen,
technologies must be developed that make solar system exploration a great
deal more economical.
The development and implementation of a biological life support system
that is responsive to the changing needs of the crew would be of enormous
significance for our ability to live in space. A major component of this
system would be plants. This is because plants are naturally self-perpetuating
and therefore remove the need for expensive and potentially unreliable
re-supply missions. Just as they do here on Earth, plants could also provide
clean air, pure water, food, pharmaceuticals and other raw materials for
the support of the crew.
However, before plants can be used for life support in space or on other
planets, we must study how they will respond and adapt to their new environment,
including lower gravity, higher radiation and other unique growing conditions.
We will be ab le to use existing plants and even create new ones, through
genetic engineering, once we gain this understanding and this will allow
us to expand our presence in the solar system to satisfy our innate desire
to delve into the unknown.
All life on Earth has evolved under the constant and pervasive force of
gravity. Space Biology as a discipline exists to determine how gravity
shapes life and, now that we are able to leave the surface of the plant,
how life responds to the absence of gravity. To do this researchers are
looking at the mechanisms by which evolution, development, cell processes,
physiological systems and organisms respond and adapt to gravity.
Do Plants Grow?
Plant growth is influenced by many environmental factors such as light,
temperature, chemicals and gravity. A plant needs to be able to sense
changes in its environment and adjust its growth in response. Plant growth
occurs when the environmental conditions are favorable. Unlike animals,
plants are rooted in the ground and are unable to relocate themsel ves
in their environment, but they can change their direction of growth. They
can move and orientate themselves to better access the environmental components
necessary to their life and development. In many instances the change
in environment, or signal, is detected in one part of the plant, but the
growth may occur in another part of the plant.
Process of Science:
Science is all
about questions. Just like all scientists, as you work through the NSCORT
activities on this site you will be progressing through the following stages:
- Making observations - What do you observe?
- Asking questions:
Do you have a question about what you observed?
- Forming a hypothesis:
What is your idea about an answer for your question?
- Testing the hypothesis:
How could you investigate your idea?
- Evaluating the hypothesis:
Did you answer the question?
The activities which follow look at how plants move,
phototropism, gravitropism and the effect of calcium on plant growth.
Scientists investigate many different experiments as a way of finding answers
to their questions and there are many different experiments you can do to
answer a question.
We have suggested a few, but you can be creative and design others!
When you are investigating your question its a good idea to:
- Remember that many factors such as light, temperature,
humidity and touch can affect plant growth and therefore your results.
So, take a few minutes to plan your experiment and try to be as consistent
- Think about how many plants you need to test
for each r esult to be representative.
- Vary only one thing at a time!
- Enjoy it!!
With special thanks to Drs C. & P. Williams, Wisconsin
Fast Plants Program, University of Wisconsin for allowing us to include
and modify their experiment on phototropism and the "processes of
Clore, J. Love, I.
Perera & S. Wyatt, NCSU-NSCORT
& Ms. Tracey Horn