Hypotheses, Theories, and Laws

Which is the best description of a scientific theory?

• a statement about how two different variables are related

• a collection of laws that are explained the same way

• an explanation of many observations and tested hypotheses

• an accepted fact that has always been observed to be true

Which of these are characteristics of a scientific law? Check all that apply.

• It contains an explanation of facts.

• It states a fact about how nature works.

• It is based on observations of nature.

• It often changes over time with new experiments and technology.

• It will most likely remain true even when scientists work with new experiments.

What is a factual statement about how nature behaves or functions?

• a hypothesis

• a law

• a theory

• an experiment

Albert Einstein changed the way we think about gravity by using the results of many new experiments to explain that giant objects like Earth bend the space around them. According to Einstein, this bending of space makes smaller objects move toward larger objects.

Which statement best explains whether Einstein’s idea is a theory or a law?

• It is a theory because it is a statement of fact that does not include an explanation.

• It is a theory because it was developed with many new experiments, and it explained the observations.

• It is a law because it is a statement of fact that does not include an explanation.

• It is a law because it was developed with many new experiments, and it explained the observations.

Which statement is most likely a scientific law?

• Animals need oxygen because it unlocks the energy contained in food

• Colonies of microscopic organisms grow faster in closed spaces because they cannot fly away.

• The oldest layers of rock lie below newer layers of rock on Earth.

• Healthy foods taste better than dangerous or spoiled foods.

While studying how objects change motion when they run into each other, Isaac Newton discovered that the force of an object’s impact equals the object’s mass multiplied by its acceleration.

He could not explain why this is, but it was clearly true to anyone else who conducted experiments, and it remains just as true today.

Is Newton’s statement a law or a theory?

• It is a theory because it developed and changed over time as new technology provide

• It is a theory because it is a statement of fact that does not need any more experimental support.

• It is a law because it developed and changed over time as new technology provided new observations.

• It is a law because it is a statement of fact that does not need any more experimental support.

What did Leeuwenhoek use that enabled him to see bacteria?

• the staining of dishes in a lab

• the heating of food and liquids

• different magnification lenses

• observations of diseased people

How did Louis Pasteur’s experiments lead to new scientific understandings of germs?

• Experiments with cooking food showed that disease-carrying germs in food could be killed when heated.

• Experiments with different magnification lenses showed that germs were real and could be observed.

• Experiments with animals showed that dominant genes could lead to risks of disease.

• Experiments with shallow dishes showed that groups of germs could be grown so they could be seen without microscopes.

What would most likely occur over time if new technologies gave us information that challenged what scientists currently understand about natural selection?

• A new scientific law would be established and proven by the findings.

• A new scientific theory would be established and proven by the findings.

• A current scientific law would be revised based on the new findings.

• A current scientific theory would be revised based on the new findings.

A scientific hypothesis is likely to be used in a new area of science, but unlike other scientific ideas, it will not likely change over time.