Describe how the “Systems” theme might apply to the scientific method. Bellwork 8/19 Describe how the “Systems” theme might apply to the scientific method.

Is the sun an organism? How do you know? Bellwork 8/20 Is the sun an organism? How do you know?

1.3 Power Notes Scientific Thinking and Processes Observing: Using the senses or tools to gather information Forming Hypothesis: Ask a question and try to explain observations - If….then….because` Testing Hypothesis: Collecting data to support or reject a hypothesis Analyzing Data: Statistical analysis of data to draw conclusions Evaluating Results: Data and conclusions are studied to determine whether they are valid

1.3 Power Notes Experiment: Using independent and dependent variables to find cause – and – effect relationships Independent variables: the condition that is manipulated; the “cause” Dependent variables: the factor that is measured; the “effect” Constants: any condition that is kept the same Control: doesn’t receive any special treatment

Different rose bushes are grown in a greenhouse for two months 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. Independent Variable: Dependent Variable: Constants:

You water three sunflower plants with salt water You water three sunflower plants with salt water. Each plant receives a different concentration of salt solultions. A fourth plant receives pure water. After a two-week period, the height is measured. Independent Variable: Dependent Variable: Control : Constants

Three redwood trees are kept at different humidity levels inside a greenhouse for 12 weeks. One tree is left outside in normal conditions. The heights of the trees are measured once a week. Independent Variable Dependent Variable Control Constants

Bellwork 8/21 Pea plant clones are given different amounts of water for a three-week period. The first 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 heights of the pea plants are recorded daily. Independent Variable Dependent Variable Control Constants

Bellwork 8/22 You are conducting an experiment to determine if increased ultraviolet radiation from the decrease in the ozone layer is killing off frog tadpoles. Group 1 involves 100 tadpoles in a five gallon container of water, which is covered by glass, which will filter out UV radiation. Group 2 will be set up exactly like group 1, except that instead of being covered with glass, it is covered with an acrylic plexiglass, which will not filter out the UV radiation. You then place the groups outside for a period of a month, and observe the results. IV: Control group: DV: Constants:

Bellwork 8/23 Shari set up plastic bowling pins .5 m from the end of a ramp. She rolled a ball down the ramp and into the pins. She then counted how many of the pins the rolling ball moved. She repeated this three more times using balls of different masses. What is the question being investigated? Identify the following: IV: Control: DV: Constants: