Robert Hooke saw the first cork cells in 1665. He also coined the word "cell" at the same time. During the next 150 years, scientists developed cell theory. They discovered cell organelles and described the cell as the basic unit of all life. One point of cell theory was NOT accepted until the early 1900's. That point was the cells give rise to other cells. For much of this time, many scientists still believed that cells just appeared. That idea was called spontaneous generation. People believed that living cells to develop from non-living things, like meat or soup.

Why did it take over 150 years for the scientific community to accept the last point of cell theory: cells give rise to other cells?

This is a timeline depicting the development of atomic ___________. What word should be used to fill in the blank? Support your choice with evidence.

A scientific law is something we can use to make a specific, concrete prediction. For example, the law of gravitation states that masses will attract each other, and you will find that this is always the case.

However, it can also be used to make concrete statements about the properties of an object in the right conditions. For example, if a material were found that was NOT attracted to other objects with masses, we could say that

Which geological features MOST LIKELY prompted the development of the theory of plate tectonics?

- prediction

- can be supported

- cannot be proved or disproved

- tested with a controlled experiment

The list of terms BEST describes a

Identify the scientific law from among the following statements.

A teacher has asked four students to state a scientific theory. Which student is correct?

Darwin observed how farmers and breeders produced many kinds of farm animals and plants. These plants and animals had traits that were desired by the farmers and breeders. He also noticed how the study of similar body structures and vestigial organs could add to the evidence of evolution. After performing several breeding experiments, he came to certain conclusions and formulated some theories. His theory of evolution and natural selection is the most accepted one.

What is the reason behind the acceptance of Darwin's theory?

A __________ predicts overall natural events in general terms, while a __________ is a very specific prediction based on one circumstance.

Scientific hypotheses, theories, and laws are all vital to the development of scientific ideas. They are all vital, but they are not equal. They actually represent different types of ideas, with varying degrees of strength. The strength of a scientific idea is based in large part on how well it allows us to predict what will happen in certain situations.

Rank the three, beginning with the weakest.

Which sentence BEST explains why scientists continually make incremental adjustments to their theories?

A scientific theory is based on

A __________ predicts overall natural events in general terms, while a __________ is a very specific prediction based on one circumstance.

Darwin observed how farmers and breeders produced many kinds of farm animals and plants. These plants and animals had traits that were desired by the farmers and breeders. He also noticed how the study of similar body structures and vestigial organs could add to the evidence of evolution. After performing several breeding experiments, he came to certain conclusions and formulated some theories. His theory of evolution and natural selection is the most accepted one.

What is the reason behind the acceptance of Darwin's theory?

- can be disproved

- supported with repeated testing

- valid if there is no evidence to dispute it

The list of terms BEST describes a

Sir Isaac Newton determined that gravity has a fixed acceleration on Earth. The earth pulls objects towards it with a fixed acceleration at -9.8 m/s2. This is a _____________ ____________, as it states a scientifically accepted fact about the natural world.

Extensively tested and generally accepted : uncertain explanation for an observation

In the early 1900s German geophysicist Alfred Wegener began to question how the structures on the Earth formed over time. He proposed the Theory of Continental Drift to suggest that all continents were once connected and have "drifted" to their current location over time.

What was the main reason that Wegener's theory received a lot of ridicule from the scientific community?

"Fifteen hundred years ago everybody knew the Earth was the center of the universe. Five hundred years ago, everybody knew the Earth was flat, and fifteen minutes ago, you knew that humans were alone on this planet. Imagine what you’ll know tomorrow.”

That's a statement of Agent Kay in from Men in Black.

Agent Kay's statement illustrates that theories are

Scientific hypotheses, theories, and laws are all vital to the development of scientific ideas. They are all vital, but they are not equal. They actually represent different types of ideas, with varying degrees of strength. The strength of a scientific idea is based in large part on how well it allows us to predict what will happen in certain situations.

Rank the three, beginning with the strongest.

A scientific theory

Which geological features MOST LIKELY prompted the development of the theory of plate tectonics?

A scientific theory is based on

A teacher has asked four students to state a scientific theory. Which student is correct?

In 1859, Charles Darwin described a model of how living things change over time. He described this model and the evidence that supported it in a book called On The Origin of Species. Which scientific term is used to describe a testable model that seeks to explain natural phenomena?

"Fifteen hundred years ago everybody knew the Earth was the center of the universe. Five hundred years ago, everybody knew the Earth was flat, and fifteen minutes ago, you knew that humans were alone on this planet. Imagine what you’ll know tomorrow.”

That's a statement of Agent Kay in from Men in Black.

Agent Kay's statement illustrates that theories are

A scientific law is something we can use to make a specific, concrete prediction. For example, the law of gravitation states that masses will attract each other, and you will find that this is always the case.

However, it can also be used to make concrete statements about the properties of an object in the right conditions. For example, if a material were found that was NOT attracted to other objects with masses, we could say that

A __________ predicts overall natural events in general terms, while a __________ is a very specific prediction based on one circumstance.

Sir Isaac Newton determined that gravity has a fixed acceleration on Earth. The earth pulls objects towards it with a fixed acceleration at -9.8 m/s2. This is a _____________ ____________, as it states a scientifically accepted fact about the natural world.