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Theory vs. Law Review

1. What example does the author (article) use to show whether or not a theory 

becomes a law?

• “So just as houses don’t become bricks, theories don’t become l h i blaws.  Both are important, but they tell us very different things.” 

2. What is a theory based on? (textbook)

• “A scientific theory is based on repeated observations and scientific investigations.”

3. What is a scientific law? (textbook)

• “A scientific law describes a pattern or an event in nature that is always true.”

4. What can happen if a hypothesis is well‐supported? (textbook)

• A well‐supported hypothesis can contribute to a theory or a law.

5. What happens if new observations are found that do not follow a scientific law? 

(textbook)

• “If many new observations do not follow the law, the law is rejected.”

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6. What can happen if a theory has a flaw or new information is discovered that does not support a theory? (article & book)

• “If new information does not support a scientific theory, the theory will be 

difi d j d ” (b k)modified or rejected.” (book)

• “Scientists would examine the new evidence, and see if there was a way to adjust the theory so that the new evidence fit.” (article)

7. How does Einstein explain the way scientists work? (article)

• “No amount of experimentation can ever prove me right; a single experiment can 

” lb i iprove me wrong.” – Albert Einstein

• Until evidence goes against the existing laws and theories, they continue to be accepted.

Theory:Theory:

• The best explanation of observations or events

• Attempts to explain 

3. What is the difference between scientific theories and laws?

Law:Law:

A statement or equation that reliably predicts patterns or events in nature

“how” or “why”something happens

• More complex than laws & can contain several supported hypotheses

• Considered universally true – does not answer “why” questions

• Usually based on 1 well‐supported hypothesis that states that something will happen

Both (theory & law):Both (theory & law):

• Based on many observations

• Can be modified or rejected with new info.

I l d ll d h h

What is the difference between scientific theories and laws?

• Includes well‐supported hypotheses

Contributing Scientists to Cell Theory

Scientists (in order) Contribution (what they discovered)

Robert HookeBuilt a microscope & looked at cork; noticed small “openings” (cells)

SchleidenLooked at plant cells (noticed they are similar to animal cells)

SchwannStudied animal cells (noticed they are similar to plant cells)

VirchowProposed that all cells come from preexisting cells

1. What is cell theory?

All living things have cells

Cell theoryCells are the

smallest unit of life

All cells come from preexisting

cells

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Definition of Cell

A cell is the smallest unit that is capable of performing life

functions.

6. What attempts to predict events in nature under certain conditions?

A. Scientific theory

B. Scientific model

C. Scientific law

A. B. C. D.

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D. Scientific hypothesis

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7. What attempts to explain why something happens in nature?

A. Scientific theory

B. Scientific model

C. Scientific law

A. B. C. D.

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D. Scientific hypothesis

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8. Which of the following do scientific theories and laws have in common?

A. Both try to explain why something happens

B. Both try to predict events in nature

A. B. C. D.

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C. Both are complex and based on several hypotheses

D. Both can be rejectedNonNon--Response Response

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