Unit 0, Nature of Science Study Guide

What is Science?

Science is the process of discovering how the natural world works. Science builds knowledge through the process of discovering how the world works.

What is a testable question?

Scientific research starts with a research question. The question MUST be testable. You must be able to collect data to help answer the question. Do horses run faster than mules? is a testable question.

What variables do scientists need to be aware of when replicating an experiment?

The variable(s) that a scientist needs to be aware of when replicating an experiment are control, dependent, and independent.

· Scientific theory is the consensus of many scientists and offer explanations about the natural world. Carl and his partner already know what the birds eat during the spring. The research is focused on seeds

a reasonable test would be a comparison of seeds eaten in the winter compared with the spring; How do the seeds eaten by birds in winter compare to seeds eaten in spring?

· Place the steps of the scientific method in correct order.

o Question o Research o Hypothesis o Experiment o Analyze Data o Conclusion

After many experiments have been done and much more data has been collected scientists can then re-evaluate the merit of theory

A theory can be changed to reflect new observations and data. Science is never static, it is continuously changing!

What does a Scientific Theory Explain?

A theory explains some aspect of the natural world based on repeated predictions, testing, and observations. It is a general explanation while a hypothesis predicts an outcome from a specific set of circumstances.

Dennie wanted to see if crayfish preferred one kind of food over another. He gave one group of crayfish plants, both living and dead, to eat. He gave the other group insects, living and dead, to eat

Dennie's independent variable was type of food.

Are ghosts testable in science?

Ghosts are not considered part of the natural world, therefor not testable in science.

The scientific method is a series of organized steps someone takes in order to solve a problem. It is broken down into a series of logical steps that make sense. Once the scientist has made sufficient observations and formed a hypothesis, an experiment must be designed. This experiment must be a controlled experiment, meaning that all variables must remain the same except for those being manipulated on purpose.

· . There are two types of variables in an experiment. Independent variables are the variables that the scientist changes on purpose. Dependent variables are those that change in response to the independent variable. Consider the following situation: A farmer wants to test different chemicals in fertilizers to see how it affects plant growth. The independent variable would be the chemicals in the fertilizer. The dependent variable would be plant growth.

What is a scientific theory?

· A scientific theory is a well-supported, widely accepted explanation.

What does a Scientific Theory Summarize

· A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing. If new evidence is found, a theory can be refuted.

Ben and Joey were making some sweet tea for their mother. They were having a hard time getting the sugar to dissolve in the water. "Let's do an experiment to see how we can make the sugar dissolve faster!"

· A testable question the boys could use for their investigation is What will help us dissolve sugar in a glass of water?

Raul and Tyree have open cans of soda. The can A is left sitting on the table while the other cans B and C are each heated on a hot plate. Can B is heated to a much higher temperature than can C. The students then monitored the cans for expansion.

· Higher temperature causes greater expansion in aluminum cans. is the most reasonable hypothesis because the students are monitoring for expansion. The control can is not heated, therefore, the variable is the heating of the cans.

Can science experiments be repeated regardless of who preforms it?

· Reliable scientific experiments can be repeated regardless of who performs the experiment.

Scientists first found dinosaur fossils about 1820. The fossils suggested that dinosaurs were large, slow, reptiles. This view was widely accepted for decades. However, in 1960, scientists began to challenge the idea. More recently, several findings showed that some dinosaurs were closely related to birds, and had active, agile bodies.

· The information provided suggests that scientists have had to revise accepted ideas of dinosaur biology. When a body of evidence goes against an accepted scientific idea, the idea usually has to be revised.

Gretchen wants to run a test to discover whether glass, copper, wood, or plastic conduct electricity. She sets up a circuit connecting a battery to a light bulb, with a small gap she will use to test the conductivity of the different substances. One at a time, she connects the circuit with the chosen test material, and records whether or not the light bulb comes on

· This is a good experimental design because when you set up an experiment, you should only be testing one difference at a time.

Liz and Michelle are testing which ball will bounce the highest. They test 4 different balls. Each ball is dropped five times from the same height. The height of the bounce is measured. At the end of the experiment, the data for each ball was averaged to obtain an average bounce height.

· This is a well designed experiment because they averaged the measurements and had multiple trials.

Are cats more active at night than during the day?

· is a testable question. By observation, data could be collected on how much time a cat is active at night and during the day. Based on the data, the evidence would support a conclusion.

The word theory in science does not mean the same thing as it does in everyday life. A theory is not a guess or a hunch. It is built upon one or more hypotheses, and upon evidence. A theory contains reasoning and logic based on the evidence observed.

·A scientific theory can be shown to be wrong through experiment or observation. One of its hypotheses might be wrong or new data might come along that disagrees with it. In science, a wrong theory can be modified or discarded.