Quiz: Thinking Scientifically!

Which of the following is a testable hypothesis?

• Roses are more beautiful than violets 
• A plant needs at least five hours of sunlight per day to grow
•  Ice cream is delicious
• Humans will someday land on Mars 

Evolution is one example of a theory. From what you know about the scientific method, what can you conclude about this biological theory? 

• It's been tested many times
• Scientists don't need to test it anymore
• No one is allowed to test whether it's true or not 
• There is very little evidence to support it 

What might cause a theory to change over time? 

• New laws passed by the government
•  New but untestable ideas
• Changes in public opinion 
•  The discovery of new evidence

What's the difference between a hypothesis and a theory? 

• "Theory" is another word for "fact;" "hypothesis" is another word for "guess"
• Hypotheses can't be proven; theories can
• Theories have been confirmed through tests; hypotheses haven't
• Theories contain many hypotheses; a hypothesis only contains one theory

What must you do before you make a hypothesis?

• Run an experiment 
• Make observations 
•  Form a theory 
• Draw conclusions 

If you were running an experiment to determine the temperature at which beans sprout the fastest, what would be the independent (manipulated) variable? 

• The number of beans you plant 
• The height of the sprouts you grow
• The amount of water you give the beans
• The temperature at which each bean is kept

Mrs. R sets up an experiment to see how the mass of a ball affects the distance it rolls off a ramp.  Identify the responding variable (dependent variable).

• height of the ramp
•  distance traveled by the ball
• mass of the ball
• weight of the ball

Experimenting on plant growth, a scientist uses three of the same type of plants, two different fertilizers,  an equal amount of daylight, and an equal amount of water. What type of variable is the fertilizer?

• Responding or Dependent
• Manipulated or Independent
• Control
• Compound

A student hypothesized that robins prefer large birdhouses to small ones. He builds four birdhouses of different sizes to test his hypothesis. What is the independent variable?

• The size of the birdhouse
• The number of birds in the house
• The location of the birdhouse
• The season of the year

A group of middle school students was given a short course in speed reading.  The teacher was curious of money could influence their performance on a test taken at the end of the course.  Half the students were offered $5 for a getting a certain percentage better at speed reading, the other half was offered no money.  Which is the dependent variable?

• Students being offered money or not.
• Their test  scores.
• Their age in school years.
• The length of the course.