Foundations of Science
Carla wanted to see if her heart rate would be higher if she did jumping jacks for 10 minutes or ran for 10 minutes. Which of the following would be the test variable (independent variable)?
A. type of exercise
B. amount of time running
C. the resting period between exercises
A. type of exercise
Scientists do many types of work. Their work often includes making field observations, conducting surveys, creating models, and carrying out experiments. Which description characterizes an experiment?
A. observation of plants or animals in their natural environment
B. data collected from uncontrolled situations in the natural world
C. physical or mathematical representation of an object or process
D. organized procedures to study something under controlled conditions
D. organized procedures to study something under controlled conditions
Which statement BEST explains why scientific knowledge improves over time?
A. Scientific data can be interpreted differently based on personal beliefs.
B. Scientific ideas change as new information is collected and interpreted.
C. Scientific theories are considered laws once they are proven by many scientists.
D. Scientific experiments can be repeated under different conditions with the same results.
B. Scientific ideas change as new information is collected and interpreted.
A statement that can be tested scientifically through experiments and/or other scientific investigations
A. Inference
B. Hypothesis
C. Observation
D. Experiment
B. Hypothesis
A class conducts an experiment to test how temperature affects the dissolving rate of sugar. What would be the outcome (dependent) variable?
A. type of sugar
B. size of container
C. water temperature
D. rate sugar dissolves
D. rate sugar dissolves
Cathy wants to know whether different colors of light affect the growth of plants. She buys four plants and places three of them under lamps with different-colored light bulbs. She places the fourth plant in natural light. Which of the following types of scientific investigations is Cathy conducting?
A. a model to represent plant growth B. a simulation to imitate plant growth
C. a field study to observe plant growth
D. a lab experiment to test a hypothesis about plant growth
D. a lab experiment to test a hypothesis about plant growth
Which step must take place before a new scientific theory can replace a previous one?
A. It must be tested many times.
B. It must be explained with a model.
C. It must be accepted as a scientific law.
D. It must be agreed upon by all scientists.
A. It must be tested many times.
The variable manipulated by the experimenter in order to study changes in the outcome variable.
A. Independent (test) Variable
B. Control Variable
C. Dependent (outcome) Variable
D. Constant Variable
A. Independent (test) Variable
Why should a scientific investigation be replicable?
A. So, it is more fun to do again.
B. So, others can guess what happened.
C. So, scientists can prove they are smarter.
D. So, results can be confirmed by repeating the experiment.
D. So, results can be confirmed by repeating the experiment.
Sara observes squirrels in a park every day, at the same time of day, for a month. She records what they eat and how often they visit trees and feeders. She doesn’t change anything about their environment. What type of investigation is Sara doing?
A. survey
B. physical model
C. controlled experiment
D. systematic observation
D. systematic observation
A group of scientists has made a new discovery about how the natural world works under certain conditions. What would have to happen before their discovery can become a scientific theory?
A. Their idea would have to become a law before becoming a theory.
B. Scientists are professionals, so it would be accepted without question.
C. They would have to keep their discovery a secret, so others do not steal it.
D. Many other scientists would have to verify these findings in order for their discovery to become a theory.
D. Many other scientists would have to verify these findings in order for their discovery to become a theory.
A factor, usually being measured or observed, that responds to, or depends on, another factor (test variable).
A. Independent (test) Variable
B. Control Variable
C. Dependent (outcome) Variable
D. Constant Variable
C. Dependent (outcome) Variable
A group of students tests how light affects plant growth. Another group at a different school repeats the same experiment using the same setup and gets nearly identical results. What does this tell us about the original investigation?
A. The plants they used were fake.
B. The experiment is boring and easy.
C. The second group copied the first group.
D. The results are likely valid and replicable.
D. The results are likely valid and replicable.
Researchers at Florida International University surveyed people to find out how many would not evacuate if a hurricane were approaching. In 1992, 18% would not evacuate. In 1995, 34% would not evacuate. In 1999, 46% said they would not evacuate.
How can scientists use this information?
A. To predict where people go when they evacuate.
B. To explain why people choose not to evacuate.
C. To predict how many people will not evacuate.
D. To predict which route people will use to evacuate.
C. To predict how many people will not evacuate.
The abbreviated timeline shows several events in history regarding DNA.
• 1869-DNA first isolated
• 1953-DNA determined to be in a double helix
• 2003-Human genome mapped
Which statement explains the timeline?
A. Theories about DNA remain the same through history.
B. DNA is more important today than in the previous years.
C. Knowledge about DNA increased as new information was discovered.
D. Modern scientists ignored DNA discoveries made by scientists in the past.
C. Knowledge about DNA increased as new information was discovered.
A scientific test or procedure that is carried out under controlled conditions to answer a scientific question.
A. Observation
B. Model
C. Experiment
D. Inference
C. Experiment
Lena conducts an investigation to find the best material to insulate a cup of hot water. She records every step, includes a list of materials, and shares her procedure and results. Why is it important that Lena included these details in her investigation?
A. Others can see how smart she is.
B. to make the experiment seem more complicated
C. to make the results secret from other investigators
D. Others can follow her procedure and test her results.
D. Others can follow her procedure and test her results.
Isaac Newton said that objects accelerate to Earth at the same rate, regardless of their mass. To test this theory, two students each drop a rubber ball and a crumpled piece of paper separately from the same height. The students use a stopwatch to time how long it takes for each item to hit the ground. Student 1 finds that the rubber ball and the paper hit the ground in the same amount of time. Student 2 finds that the rubber ball and the paper hit the ground in slightly different amounts of times. Why did the students get different findings?
A. Newton’s theory must be wrong.
B. Another variable may have contributed to the results.
C. Student 2 must have used a different scientific method.
D. Student 1 must have made a mistake during the experiment.
B. Another variable may have contributed to the results.
From ancient times the circulatory system was known to be central to an animal's ability to live. An early scientist named Claudius Galenus or Galen studied the organs that circulated blood. He wrote that blood was produced in an animal's liver, moved through arteries and veins in separate systems, and was used up by the organs. Thus, new blood had to be made for each cycle. A scientist named Thomas Harvey, however, found that while blood does flow through the arteries and veins, the heart and liver do not produce blood. Instead, the heart pumps blood in a circular path through the body, allowing blood to be reused many times. Which statement BEST describes Galen's ideas about the circulation of blood?
A. Galen's ideas were not testable.
B. Galen's ideas were refined over time.
C. Galen's ideas were not based on observations.
D. Galen's ideas were accurate for only some animals.
B. Galen's ideas were refined over time.
A factor or condition in a scientific experiment that is purposefully kept the same.
A. Independent (test) variable
B. Dependent (outcome) variable
C. Constant
D. Controlled Variable
D. Controlled Variable