In this unit WE will review the steps of the scientific method and practice using science in everyday life. On the following slides, the red sections are the main points; summarize the slides in your notebooks. Underline words = vocabulary! §112 The Nature of Science

Notes – The Cornell Method For this class, place the topic or guiding question in the left hand column. As you get more skilled, you will create your own topics and questions. Summarize the notes in the right hand column: –NO complete sentences –Abbreviations –key phrases –Sketches + drawings

Defined by the National Academy of Sciences, it is the "use of evidence to construct testable explanations and predictions of natural phenomena, as well as the knowledge generated through this process." Science is the organized way of using evidence to learn about the natural world. The goals of science: –to investigate –to predict future events –to explain natural events content/uploads/2008/06/img_0255.jpg What is Science?

Observing uses one or more of the five senses (sight, hearing, touch, smell, & taste) to gather information about events or processes. Observing allows you and scientists to gather information about the subject they are investigating. Skills in Science Tiff Shao, a NYC native and biology major, is studying biodiversity in Costa Rica for Duke University’s Organization of Tropical Studies. Although Tiff is far from Duke, the classroom is not too far away. LinkLink

Through observing, scientists collect information, called data. Scientists then use this data to make inferences. An inference is an interpretation based on data and observations or prior knowledge. A prediction is a statement or claim that a particular event will occur in the future (EX the weather). Skills in Science Cont. This image is view of the meteorological data collected for weather stations and used by forecasters to predict the weather. Link Link

Scientific Method The scientific method is a procedures that scientists use to answer a question: 1.Purpose/Problem 2.Hypothesis 3.Experiment 4.Data Collection 5.Analysis 6.Conclusion EmHg8/s400/scientific+method.gif

Purpose or Problem Typically after making an observation a scientist will begin to question why? What problem do you want to solve? What do you seek to learn? You must research is already known about the problem.

Hypothesis A hypothesis is a possible explanation or answer to a scientific question, often called an educated guess. A hypothesis must be testable and capable of being supported by observable evidence; the evidence typically comes from an experiment.

An experiment tests the hypothesis to see if it is correct. Scientists: –use instruments that measure and collect data –keep detailed notes on the procedures, so the experiment can be duplicated –repeat the experiment through several trials for the most accurate data possible Experiment

The information from an experiment is data. –qualitative descriptive (EX color, odor, or sound) –or quantitative numerical (EX #s). Data This image above provides qualitative data while the image below provides quantitative data during an experiment (Link).Link

Scientists analyze (look closely at) the data and study the results. Scientists determine how to represent that data, whether in charts, graphs, tables, etc. Analysis

At the conclusion of the experiment, the scientist asks, “What did I learn?” and discusses the results of their analysis. A conclusion states whether or not the hypothesis was correct. Often the data does not support the hypothesis which means the whole process can start over again with new questions to be answered! Conclusions

Types of Experimental Investigations: 1.Descriptive – based mainly on observations –No controlled variables –EX making models, dissections, observing animals in the wild Jim and Jamie Dutcher spent six years in Idaho in a tent within the world’s largest wolf enclosure in order to observe and document the behavior of these wild animals. They got really close to the wolves and made many unique photos of wolves in their natural habitat (Link).Link

Types of Experimental Investigations Cont: 2.Comparative - involve collecting data on different groups under different conditions –to make comparisons –EX two plants - one with fertilizer, one with a different fertilizer

3. Experimental - the manipulation of variables –variables are actively manipulated –EX rye grass seeds in three cups, 1watered daily, 1watered every other day, 1 without water (control) Types of Experimental Investigations Cont:

A controlled experiment is an experiment in which all factors except one remain constant (are the same). What is a controlled experiment?

In order for an experiment to test only one variable, other parts of the experiment must be the same. These are constants. Some experiments involve a control group; the control receives NO treatment and is used to compare. How do scientists control variables? ITECH.jpg

The variable the scientist changes is called the independent ( or manipulated) variable. “I, the scientist” = independent variable Independent (AKA Manipulated) Variable

The variable that is expected to change in response is the dependent (or responding) variable. The “data I collect” = dependent variable; it is what we measure. Dependent (AKA Responding) Variable /img33.gif

Vocabulary in Action! –Independent Variable = “I the scientist” am controlling the temperature of the water. –Dependent Variable = Speed of diffusion of the food dye. Independent Variable!!! Dependent Variable!!!

What Graph? The type of graph you will use depends on the type of data in your experiment. –Line – use for infinite data (i.e. time) –Bar – static or finite data (i.e. number of days in a week) –Pie – good visual for %

Reading A Graph Graphs allow us to interpret data and predict by reading carefully. How would interpret the line graph presented here? “NASA released data showing this last meteorological year to be the hottest ever in their 130 year records. The meteorological year, which ended on November 30th, boasted a global average temperature of 14.65°C. This was an increase of 0.12°C on the previous warmest year, 2005, which had a global average of 14.53°C. The average is taken by measuring temperatures both over land and sea…” By Jonathan Frost, 2010: the hottest year on record (Link).Jonathan FrostLink

Remember scientists show their data in graphs. Remember the acronym DRY MIX when graphing for science. –Dependent/Respondin g variable = Y axis. –Manipulated/Independ ent = X axis. Sketch the graph to remember the axes. DRY-MIX Independent Variable!!! Dependent Variable!!!

A hypothesis is a tentative, testable statement for a specific problem or question. A scientific theory and is well- established, highly-reliable explanations of events [natural and physical] from multiple, independent theorists. –Atomic Theory –Cell Theory –Theory of Evolution Theories may change as new areas of science and new technologies are developed, providing new information. What is the difference? This powerful electron microscope allows researchers to see tiny microbes and cells as never before; the system includes a camera to record the data. Link Link

The scientific method will be used throughout the year during our class experiments. Scientists study the world through experiments using very similar procedures and steps. As scientists in this classroom, safety is the number one priority! Unit Conclusion px.jpg