Unit 1: The Scientific Method & Experimental Variables

Sharon observed that plants seemed to grow faster when they were near high concentrations of carbon dioxide. Sharon decides to conduct a controlled experiment based on her observation. In which order should Sharon perform the remaining steps of the Scientific Method:

1) Interpret data and display results

2) Perform a controlled experiment

3) Draw conclusions

4) Form a hypothesis

• 2, 4, 3, 1

• 4, 2, 1, 3

• 3, 1, 2, 4

• 4, 2, 3 ,1

Which of the following is an example of quantitative data?

• The test tubes contain acid.

• The test tubes are bubbling.

• The level of the solution is the same .

• The temperature in Test Tube B is 20^o C.

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NGSS.MS-PS3-1

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In 1927, the geneticist Hermann Muller exposed flies to ultraviolet light. He found that the flies’ offspring displayed many mutations. He concluded that the ultraviolet rays caused chromosome breakage, which caused the mutations.

What was the independent (manipulated) variable in Muller's experiment?

• Chromosomes

• Ultraviolet light

• Mutations

• Flies

Anita hypothesizes that if plant seeds are soaked in water, then the seeds will sprout faster. How should Anita conduct her controlled experiment to obtain results that will allow her to support or to reject her hypothesis?

• Grow 100 seeds soaked in water

• Grow 50 each of two types of seeds that were soaked in water

• Grow 50 soaked seeds and 50 not soaked seeds

• Grow 100 soaked seeds and 50 not soaked seeds

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NGSS.MS-LS1-5

Juan observes that a potted plant on his desk is bending toward the nearest window. Which hypothesis would be best for Juan to investigate the reason the plant is bending?

• If the plant gets more fertilizer and water, then it will begin to grow straight.

• The plant is bending because it needs more fertilizer.

• If the plant is placed outside, then it will begin to grow straight.

• The plant might grow straight if it is tied to a straight stick.

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NGSS.MS-LS1-5

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How many variables are manipulated (changed) in a controlled experiment?

• One

• Two

• Three

• As many as are needed

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NGSS.MS-PS2-2

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Nick wanted to see how high identical ice cubes would float in different temperatures of water. What is the DEPENDENT variable?

• Amount of water

• Size of the ice cubes

• Temperature of water

• Height of the ice cubes

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NGSS.MS-PS3-4

Tim and Moby increased the amount of sunlight that plants C & D received to determine if those plants would grow taller than plants A & B. What type of variable is the sunlight?

• Controlled (constant) variable

• Independent (manipulated) variable

• Dependent (responding) variable

• All of the Above

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NGSS.MS-LS1-5

NGSS.MS-LS2-1

Tim and Moby increased the amount of sunlight that plants C & D received to determine if those plants would grow taller than plants A & B. What type of variable is plant growth?

• Independent (manipulated) variable

• This is not a variable

• Controlled (constant) variable

• Dependent (responding) variable

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NGSS.MS-LS1-5

NGSS.MS-LS2-1

Tim and Moby increased the amount of sunlight that plants C & D received to determine if those plants would grow taller than plants A & B. All plants received the same amount of water. The water is a _________.

• independent (manipulated) variable

• experimental group

• dependent (response) variable

• control variable/constant

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1