Identifying Variables
DRY
Dependent - Responding - Y axis: Graphing
The number of daylight hours depends upon the time of year. Daylight hours increase from December to June and decrease from June to December.
Examine the graph comparing Number of Daylight Hours During a 12 Month Period. How are the variables related?
4th plant (no extra water)
Identify the control group. Pea plant clones are given different amounts of water for a three-week period. One pea plant receives 400 milliliters a day. The second pea plant receives 200 milliliters a day. The third pea plant receives 100 milliliters a day. The fourth pea plant does not receive any extra water; the plant only receives natural ways of receiving water. The height of pea plants is recorded daily.
Tree kept outside of greenhouse
Identify the control group. Three redwood trees are kept at different humidity levels inside a greenhouse for 12 weeks. One tree is left outside in normal conditions. Height of the tree is measured once a week.
The plant with pure water.
Identify the control group. You water three sunflower plants with salt water. Each plant receives a different concentration of salt solutions. A fourth plant receives pure water. After a two- week period, the height is measured.
Used a clock to test battery.
Identify the controlled variable. Emily wanted to see what battery lasted the longest. She put each battery into a clock and recorded the time that the clock stopped. She used Duracell, Energizer, Kroger brand, and EverReady.
The number of flowers on each bush.
Identify the dependent variable. Different rose bushes are grown in a greenhouse for two months. The number of flowers on each bush is counted at the end of the experiment.
time that clock stopped
Identify the dependent variable. Emily wanted to see what battery lasted the longest. She put each battery into a clock and recorded the time that the clock stopped. She used Duracell, Energizer, Kroger brand, and EverReady.
Height
Identify the dependent variable. Pea plant clones are given different amounts of water for a three-week period. One pea plant receives 400 milliliters a day. The second pea plant receives 200 milliliters a day. The third pea plant receives 100 milliliters a day. The fourth pea plant does not receive any extra water; the plant only receives natural ways of receiving water. The height of pea plants is recorded daily.
Height
Identify the dependent variable. Three redwood trees are kept at different humidity levels inside a greenhouse for 12 weeks. One tree is left outside in normal conditions. Height of the tree is measured once a week.
Height (don't say growth when given a measurable observation)
Identify the dependent variable. You water three sunflower plants with salt water. Each plant receives a different concentration of salt solutions. A fourth plant receives pure water. After a two- week period, the height is measured.
The different rose bushes
Identify the independent variable. Different rose bushes are grown in a greenhouse for two months. The number of flowers on each bush is counted at the end of the experiment.
different batteries
Identify the independent variable. Emily wanted to see what battery lasted the longest. She put each battery into a clock and recorded the time that the clock stopped. She used Duracell, Energizer, Kroger brand, and EverReady.
Amount of water.
Identify the independent variable. Pea plant clones are given different amounts of water for a three-week period. One pea plant receives 400 milliliters a day. The second pea plant receives 200 milliliters a day. The third pea plant receives 100 milliliters a day. The fourth pea plant does not receive any extra water; the plant only receives natural ways of receiving water. The height of pea plants is recorded daily.
Humidity levels
Identify the independent variable. Three redwood trees are kept at different humidity levels inside a greenhouse for 12 weeks. One tree is left outside in normal conditions. Height of the tree is measured once a week.
Concentration of salt solution.
Identify the independent variable. You water three sunflower plants with salt water. Each plant receives a different concentration of salt solutions. A fourth plant receives pure water. After a two- week period, the height is measured.
Same type of plant. (pea plant)
Identify the only controlled variable identified in the experiment. Pea plant clones are given different amounts of water for a three-week period. One pea plant receives 400 milliliters a day. The second pea plant receives 200 milliliters a day. The third pea plant receives 100 milliliters a day. The fourth pea plant does not receive any extra water; the plant only receives natural ways of receiving water. The height of pea plants is recorded daily.
Same type of plant (sunflower) and same time period (2 weeks)
Identify two controlled variables given in the experiment. You water three sunflower plants with salt water. Each plant receives a different concentration of salt solutions. A fourth plant receives pure water. After a two- week period, the height is measured.
Time (12 weeks), same type of tree
Identify two controlled variables in the experiment. Three redwood trees are kept at different humidity levels inside a greenhouse for 12 weeks. One tree is left outside in normal conditions. Height of the tree is measured once a week.
Time (two months), location
Identify two controlled variables. Different rose bushes are grown in a greenhouse for two months. The number of flowers on each bush is counted at the end of the experiment.
MIX
Manipulated - Independent - X axis: Graping
TAILS
Title - Axes - Intervals - Labels - Scale: Graphing
control group
a part/group in an experiment used for comparison
experimental group
a part/group in an experiment used for testing
dependent variable
the part of the experiment that is affected by the independent variable. Is measured/the outcome
independent variable
the part of the experiment that is changed by the scientist
controlled/constant variable
the part of the experiment that is kept the same throughout
