What is Science?/ Scientific Knowledge

Scientists think that about 65 million years ago, an asteroid struck Yucatan, Mexico, and created a huge cloud of dust in the atmosphere. The dust contained iridium, an element commonly found in asteroids. The dust cloud blocked the sunlight, killing most of the plants on Earth. Plant-eating dinosaurs starved and, without herbivores as prey, meat-eating dinosaurs died, too. Scientists studied layers of rock from around the time of the strike to confirm their hypothesis. What evidence would support the hypothesis that an asteroid's impact could have contributed to the extinction of the dinosaurs?

a rock layer containing greater than usual amounts of iridium

Karsten is researching a recent, controversial scientific issue. Which of these sources is a reliable source for Karsten to use for unbiased scientific information?

a scientific journal with peer-reviewed articles

Which personal trait stimulates scientists to develop questions about the natural world? A. creativity B. curiosity C. objectivity D. skepticism

curiosity

Which of the following best supports a scientific explanation? A. personal bias and the opinion of the scientist B. hypothesis formed after initial observations C. imagination and originality of the hypothesis D. experimental data obtained by using technology to get objective measurements

experimental data obtained by using technology to get objective measurements

According to the current theory regarding the extinction of the dinosaurs, the extinction was triggered by the effects of a large meteor that struck Mexico 65 million years ago. What is the best evidence of this theory?

magnetic mapping of rocks that reveals a buried crater in Mexico

Which personal trait do scientists mainly depend upon when they design an experiment? A. creativity B. determination C. objectivity D. skepticism

Creativity

Science

systematic study of natural events and conditions

Scientists are extremely observant when they examine the natural world. What information do scientists collect when they observe the natural world?

Data

Geologist Alfred Wegener believed that all the land on Earth once formed a giant continent called Pangaea. Wegener theorized that Pangaea broke apart into smaller continents that moved away from each other. This theory is called continental drift. Which best supports the theory that today's continents were once part of a larger landmass that broke up and drifted apart?

The Atlantic coastlines of South America and Africa fit together like jigsaw pieces.

When scientists obtain new information, what happens to an existing scientific theory?

It is reevaluated.

A scientist graphs the mass and volume of three samples, Which personal trait does the scientist need when attempting to analyze data like the information like the information mentioned above? A. curiosity B. imagination C. logic D. skepticism

Logic

Astrology is an example of pseudoscience. Astrologists use horoscopes that are based upon the positions of planets and stars to make predictions about a person's life. How is science different than pseudoscience?

Pseudoscientific conclusions are not supported by data gathered using scientific methods.

In the 1950s, a scientist conducted a study on the changes in a population of moths. Dead moths of the same species, but of two different color types were fastened to trees to study which color of moth was most likely to be eaten by birds. On dark trees, the light moths were eaten. On light trees, the dark moths were eaten. Other scientists criticized the investigation because birds' food choice using live moths should also have been studied. Which personal trait prompts scientists to question the validity of an investigation? A. creativity B. determination C. imagination D. skepticism

Skepticism

Many scientists study climate theory and ways that Earth's climate may have changed throughout its history. Researchers in Antarctica study ice samples that are thousands of years old. Why would they study samples of ancient ice?

They are seeking evidence of past atmospheric composition.

What limits what scientists can study in their work?

They can study only phenomena that they can observe or model.