The Scientific Method By Miranda Simmons

Essential Question: How do scientists pose and answer questions about nature?

The Scientific Method The scientific method is a procedure that scientists use to solve a problem.   It is a process of inquiry that involves observations, questions, hypotheses, predictions and test of predictions.

1. Identify the problem. Make an observation—information gathered using the senses. Based on that observation, you can then ask a question. The problem is always stated in the form of a question.

2. Research the problem. Do some background research to see what you can find out about the problem in question.

3. Form a hypothesis. If… …then Now that you have done a little research, you can form an “educated” guess as to what you think the solution to the problem is. Must write in “if… then… statement” (cause and effect)

4. Test the hypothesis. There can only be one variable to test. Design and perform an experiment to test the hypothesis. There can only be one variable to test.

Not like this though.

5. Collect, record, and analyze data.

6. Draw a conclusion. If your conclusion does not support your hypothesis, then, you must start over and come up with a new hypothesis.

If the conclusion does not support the hypothesis, the scientist forms another hypothesis and tests it again. If the conclusion supports the hypothesis, the experiment should be repeated many times. The hypothesis may then become a theory or a scientific law.

The scientific process is NOT just used by scientists. You use it most everyday whether you realize it or not! Here is an Example!

1. Identify the Problem. Why won’t my car start? Don’t cry! Use the scientific method to figure out why!

2. Do some background research.

3. Form a hypothesis If I change the battery, then my car will start.

4. Now test your hypothesis with an experiment. What is an EASY EASY test (experiment) that you can perform to see if the battery is dead? Check to see if the lights come on! OR Check to see if the radio comes on!

5. Collect, Record and Analyze the Data. In this case, it is as simple as making a mental note that the lights did or did not come on! Hmmm, the lights did come on!

6. Draw a Conclusion. The car’s battery is not the reason why my car won’t start. In this case, the conclusion does not support the hypothesis.

So now what??? You must form a new hypothesis! If the conclusion does not support the hypothesis, then you still have the problem. You must form a new hypothesis!

Form a New Hypothesis. If I put gas in my car, then it will crank.

Now test your hypothesis with an experiment. What is an EASY EASY test (experiment) that you can perform to see if the car is out of gas? Check the gas gauge! Add gas! OR

Collect, Record and Analyze the Data. In this case, it is as simple as making a mental note that the car does or does not crank after gas has been added! Hmmm, the car will crank now!

In this case, the conclusion does support the hypothesis. Draw a Conclusion. The car would not start because it was out of gas. In this case, the conclusion does support the hypothesis.

Problem is solved! The End

Think! Can you can name all six steps?

Steps of the Scientific Method Hey, did you get all that? Steps of the Scientific Method _______ ___ ______ _________the problem Form a _________ _____ the hypothesis (with a what?) 5. Collect, record and ________ data. 6. _____ __ _________ Identify the problem Research hypothesis Test analyze Draw a conclusion

Okay, do it again! Step 2 Step 1 Step 3 Step 5 Step 4 Step 6

How did you do? Identify Problem

How did you do? Research Problem Identify Problem

How did you do? Research Problem Form hypothesis Identify Problem

How did you do? Research Problem Form hypothesis Identify Problem Test hypothesis

How did you do? Research Problem Form hypothesis Identify Problem Collect, record, analyze data Test hypothesis

How did you do? Research Problem Form hypothesis Identify Problem Collect, record, analyze data Test hypothesis Draw conclusion

Steps of the Scientific Method Identify the problem Research the problem Form a hypothesis Test the hypothesis 5. Collect, record and analyze data 6. Draw a conclusion

Parts of an Experiment

Parts of an Experiment – The Variables There are 3 types of variables   Independent variable – variable that you change (the cause); Dependent variable – variable that changes as a result of what you changed or manipulated in the experiment (the result). This is what you want to measure Controlled variables –(a.k.a. constants) are variables or factors that remain unchanged throughout the experiment

Problem: Do plants require sunlight in order to live?

Experiment: Procedure Place one plant in sun light. Place one plant in darkness.

What is the independent variable for this experiment? LIGHT!

What is the dependent variable? It’s the life of the plant. Its whether the plant lives or dies.

What are some control variables? Same kind of plant. Same kind and amount of fertilizer. Same amount of water. Same temperature.

Other Control Variables Same size plants. Same type soil. Same starting healthy condition.

Can you name even more control variables? Same watering and feeding time each day. Same size pot. Same amount of soil.

Another Example Problem: Do students perform better on tests while listening to music?

Experiment: Procedure One group of students gets the music. The other group of students do not get music played while taking their test.

What is the independent variable for this experiment? Music!

What is the dependent variable? The test grades.

What are some control variables? Same test. Same type of room temperature & environment. Same amount of time to take test.

Parts of an Experiment – The Groups The control group – is NOT exposed to the IV. Used for comparison to show that that the result of an experiment is really due to the condition being tested. The experimental group – group that will receive experimental (independent) variable.

Parts of an Experiment – The Data The data – info. gathered from observations during an experiment. Two types: 1. qualitative- collected through the senses ex. color, texture, general properties 2. quantitative involves numbers (quantity) or measurements - ex. how much?

Qualitative Data Qualitative data - collected through the senses ex. color, texture, general properties. Qualitative data are descriptions in words It is based on some quality of an observation, such as sight, sound, color, odor, or texture.

Quantitative Data Quantitative involves numbers (quantity) or measurements - ex. how much? Quantitative data are numeric measurements. The data is objective—they are the same no matter who measures them. It includes measurements such as mass, volume, temperature, distance, concentration, time or frequency.

Suppose that a marine biologist observes the behavior and activities of dolphins. She identifies different dolphins within the group and observes them every day for a month. She records detailed observations about their behaviors. Some of her observations are qualitative data and some are quantitative data.

Qualitative data examples Dolphin colors range from gray to white. Dolphins in a pod engage in play behavior. Dolphins have smooth skin.

Quantitative data examples There are ten dolphins in this pod. Dolphins eat an equivalent of 4-5% of their body mass each day. The sonar frequency most often used by the dolphins is around 100kHz.

Identify Data Types Suppose that you are a biologist studying jackals in their natural habitat in Africa. You observe their behaviors and interactions, and take pictures of their interactions to study later. Examine the photo & give: *3 examples of qualitative data *3 examples of quantitative data

Identify Data Types Examine the photo & give: Suppose a team of scientists is studying the migration of animal species in Africa. One of the scientists takes this photograph. Examine the photo & give: *3 examples of qualitative data that could be collected during this research *3 examples of quantitative data

Theory v.s. Law Theory – well tested explanation of how something in nature works; it is well supported. Ex. theory of the disappearance of the dinosaurs Scientific Law – A rule of nature that states a fact, but does not attempt to explain it. Ex. Newton’s 3 laws of motion

Science and Technology

*Science does not address things that cannot be tested, such as beauty or ethics.   *Science deals only with hypotheses that are testable and subject to modification as knowledge and methods of testing advance. * Hypotheses that are not testable, such as those involving supernatural causes, lie outside the realm of science.

Also, unapproachable by science are questions such as, What is the spiritual meaning of life? * The quest for answers to questions like this lie in the realms of philosophy and religion.

Science, technology and society are connected in important ways Technological advances stem from scientific research, and research benefits from technology. The goal of science is to understand natural phenomena. The goal of technology is to apply scientific knowledge for some specific purpose.   Scientists often speak of discoveries. Engineers often speak of inventions.

The beneficiaries of those inventions also include scientists, who use new technology in their research. And scientific discoveries often lead to the development of new technologies. Science is driven by curiosity, whereas technology is driven by the needs and wants of people and on the social environment at times.

Technology has improved our standard of living in ways, but not without having adverse consequences. Technology that keeps people healthier has enabled Earth’s population to grow more than tenfold in the past three centuries, to more than 7 billion

The environmental effects of this population growth can be devastating: Global warming Toxic wastes Acid rain Deforestation Nuclear accidents Extinction of species

Science can help us identify such problems and provide insight into what course of action may prevent further damage.   But solutions to these problems have as much to do with politics, economics, and cultural values as with science and technology.

Now that science and technology have become powerful aspects of society, every citizen has a responsibility to develop a reasonable amount of scientific literacy.   The science-technology-society relationship is an important aspect of a science course.

Why study science? Your knowledge of science can help you make informed decisions about issues involving endangered species, biotechnology, medical research, and pollution control, to name a few.

Connections to Everyday Life:   birth and death human population nutrition, exercise and dieting medical concerns of all kinds agriculture, including forestry biodiversity and endangered species pollution and environmental changes due to global warming.

Science and Your Health An understanding of science on many different levels—genetic, chemical, and cellular, for example—can help you make any number of lifestyle choices that affect your health. Why is it important to wear sunscreen? What are the benefits of exercise? What are the effects of using alcohol, illegal drugs, and tobacco? Cigarette smoke does not just affect the lungs; it can also change a person’s body chemistry. Lower levels of monoamine oxidase in the brain can affect mood and lower levels in the liver could contribute to high blood pressure.

Biologists and other scientists research environmental issues such as pollution, biodiversity, habitat preservation, land conservation, and natural resource use, but decisions about the future are not in the hands of scientists. It is up to everyone to make decisions based on evidence and conclusions from many different sources.

Many technological advances stem from the scientific study of life. Evaluating everyday reports in the popular press about a large range of subjects requires critical thinking and some familiarity with many areas of biology.

Some News Issues Related to science Global warming Air and water pollution Endangered species Genetic engineering Test tube babies Nutrition Aerobic exercise Weight control Medical advances AIDS and the immune system

Evolution is connected to our everyday lives Evolution is the core theme of biology. Evolution tells us that all living species are descendants of ancestral species that have become modified as natural selection adapts populations to their environments. As environments change, populations change.

Biologists now recognize that differences in DNA among individuals, populations, and species reflect the pattern of evolutionary change. Evolution teaches us that the environment matters because it is a powerful selective force for traits that best adapt populations to their environment. Evolution affects everyday life in medicine, agriculture, forensics, and conservation. Environmental changes are powerful selective pressures on the adaptive traits of many populations.

The End

Test the hypothesis (with an experiment) Did ya? Huh? Did ya??? Identify the problem Research the problem Form a hypothesis Test the hypothesis (with an experiment) 5. Collect, record and analyze data 6. Draw a conclusion