Its called the independent variable I think.
1. Suzie's hypothesis (i.e. prediction of results) is that ferns which are placed in white light will grow to a taller height after two weeks than ferns which are placed in other coloured light or in a closet.
2. Her independent variable (the thing she changes to produce a result) is the kind of light that she places each plant in.
3. The dependent variable (the thing she measures) is the height of the plants after two weeks.
4. I would say her control group would be the plant placed in the closet, because every other group is exposed to some form of light.
5. I would say that Suzie has 4 experimental groups: white, red, blue, and green light.
6. The constant variables were the amount of water each plant was given, the initial height of the plants, the age of the plants, the species of fern, and what she planted the ferns in.
7. To determine how each fern did, Suzie could measure the height in addition to noting the appearance of all the plants. E.g. did any look paler than the others?
1. Several places in your digestive system secrete enzymes
2. Enzymes play an important role in every function in the human body
3. Enzymes help with nutrient absorption
