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Ohsm science1 q1 m1

  1. 1. INTEGRATED SCIENCE IQuarter 1 The Scientific Method and MatterModule 1 The Scientific MethodYou will study the following topics in this module:Lesson 1 - Formulating a Research Problem and HypothesisLesson 2 - Planning the Investigation, Experimentation and Data AnalysisLesson 3 - Making Conclusions and Recommendations EXPLORE Your UnderstandingIn this phase, you will be given an overview of the scientific method. Yourunderstanding of basic and integrated science processes gained from elementaryscience will also be assessed.Pre-AssessmentA. Directions: Choose the letter of the correct answer. Write your answers on a separate sheet. 1. How is a hypothesis tested? a. by using the hypothesis to make predictions about a system. b. by comparing observations in nature with predictions c. by conducting an experiment and looking for results d. All of the above 2. Which of the following statements would be true of the scientific method? a. People structure their lives on the principle of scientific method. b. The scientific method is a continuous process by which people learn about his world. c. Scientists report the experimental results, but not the experimental design. d. When the results of the experiment do not fit the hypothesis, a scientist may discard the results and stop the experiment. 1
  2. 2. 3. Suppose your mother sent you to the market to buy fruits and vegetables. How would you choose good quality fruits and vegetables? a. Ask the vendor to choose it for you. b. Examine the fruit if it is free from insect bites and the smell of insecticide. c. Just get any kind and pay right away. d. Tell your mother that you do not know how to buy good quality fruits and vegetables. 4. When scientists wish to communicate the results of their research, they are most likely to do which of the following? a. immediately repeat the research b. call a press conference c. write a concise report with complete results and proofs to the experiments performed and formulate conclusions d. sell their findings to other researchers 5. During an experiment about a coin and feather that were dropped at the same time, it was found that the coin reached the ground first. One student said: “Maybe, the coin is heavier than the feather.” What do you call this kind of statement? a. a problem b. a hypothesis c. an interpretation d. a conclusionB. Identification. For Numbers 6 – 10, identify what science processes are revealed in the following statements: Write your answer on the space provided after the number. communicating inferring interpretation experimenting hypothesizing observation generalization identifying the problem 6. A girl is standing in an open field. There is no shadow formed because it is 12 noon. ____________________ 7. Blue litmus paper turned red when it was dipped into an unknown liquid. ____________________ 8. The liquid in the test tube is an acid. ____________________ 9. The laptop computer is not functioning anymore. Maybe the battery got discharged. ___________________. 10. A nail turned rusty. What made it that way? ________________ 2
  3. 3. C. Directions: Read the following story, and then follow the directions below. A science student conducted a study of the ability of vertebrate blood to carry oxygen. He believed that a low environmental temperature would cause the organisms blood to carry less oxygen than blood at a higher temperature. The following reflects the student’s experiment and the data he collected.  Two tanks of salt water, each containing 25 gallons, were set up in the lab.  Each tank was filled with the same types of organisms (perch and salmon).  The same type of aerators was added to each tank to supply dissolved oxygen to the fish.  To one of the tanks, marked TANK A, the temperature was decreased at increments of 5 degrees C every 20 minutes.  The second tank, marked TANK B, the temperature was raised at increments of 5 degrees C every 20 minutes.  Blood was removed from each of the fish and measured for its oxygen content.  Below are the results from the above experiment Amount of Dissolved Amount of DissolvedTemperature Temperature Oxygen found in fish in Oxygen found in fish in in 0C in 0C Tank A (ppm) Tank B (ppm) 25 35 25 35 20 30 30 32 15 23 35 39 10 12 40 35 5 8 45 201. What is the hypothesis of the above experiment?______________________________________________________________________________________________________________________________________2. Is the above experiment a controlled experiment? Explain your answer.______________________________________________________________________________________________________________________________________3. What is the variable factor in the above experiment? _____________________________________________________________________________________________________________________________________ 3
  4. 4. 4. Graph the data above and then answer the questions that follow. Table 1 35 40 45 50 Temperatures in degree Celsius 20 25 30 15 10 5 5 10 15 20 25 30 35 40 45 50 55 60 Amount of Dissolved Oxygen found in fish in Tank A -ppm Table 2 35 40 45 50 Temperatures in degree Celsius 20 25 30 15 10 5 5 10 15 20 25 30 35 40 45 50 55 60 Amount of Dissolved Oxygen found in fish in Tank B -ppm5. What is the dependent variable? ____________________________________6. What is the independent variable? ____________________________________7. Based on the above data, is the scientist’s hypothesis correct? Explain.______________________________________________________________________________________________________________________________________ 4
  5. 5. 8. What are the controls used in the above experiment?______________________________________________________________________________________________________________________________________ KWL ChartBefore you begin with the next part of this module, fill in the first two columns. Fill inthe last column after completing the module. Matter What I know What I want to know What I learnedYou have just finished the first phase of this module. As you proceed to the nextactivities, think of a product output that will enable you to show your understanding ofthe scientific method. This product will be presented in the last part of this modulewhich will be assessed based on the following criteria: a) Community-based b) Application of Scientific MethodAs you proceed with the rest of the activities, always have this question in your mind,“When do scientific methods become valuable”.Your understanding of the scientific method will be increased as you study thelessons and perform the activities in the FIRM UP phase. 5
  6. 6. FIRM UP Your Understanding In this phase, varied learning experiences shall be introduced tohelp you understand scientific methods and equip you with skills and knowledge foryou to be successful throughout the topic. This involves acquiring scientificknowledge using scientific methods and processes. This also involves understandingor making meanings out of the scientific knowledge obtained.Scientific Method: An OverviewThe scientific method attempts to minimize the influence ofbias or prejudgment in the experimenter. It results frompersonal beliefs, as well as cultural beliefs, which meansany human filters information based on his or her ownexperience. Unfortunately, this filtering process can cause ascientist to prefer one outcome over another. For someonetrying to solve a problem around the house, succumbing tothese kinds of biases is not such a big deal. But in thescientific community, where results have to be reviewed andduplicated, bias must be avoided at all costs.Thats the job of the scientific method. It provides an objective, standardizedapproach to conducting experiments and, in doing so, improves their results. Byusing a standardized approach in their investigations, scientists can feel confidentthat they will stick to the facts and limit the influence of personal, preconceivednotions.The illustration below shows the cyclic presentation of basic procedures of scientificmethod. As you go on further with the lesson, you will be able to understand eachstep clearly as you do the given activities in each lesson. 6
  7. 7. The scientific method requires observations of nature to formulate and testhypotheses through experimentation. The record data from the experiment willdetermine the correctness of your hypothesis. Further observation andexperimentation are needed if the hypothesis is incorrect.Lesson 1 - Formulating Research Problem and HypothesisProblem solving is an important survival skill for people of all ages. Early humanbeings were forced to problem solve to ensure the evolution of humanity. Thisproblem solving skill has helped people produce all the conveniences and comfortsin life. These include the rapid improvements in our communication, transportation,medicine, and many more.But nowadays, we are given fewer and fewer opportunities to problem solve forourselves because as a society we have grown accustomed to fixing other peoplesproblems. Assisting others is admirable, but not at the expense of that persons wellbeing. We still need to develop skills that would enable us to investigate phenomenaand acquire new knowledge, as well as correcting and integrating previousknowledgeIn this lesson, you will learn the scientists’ recommended step by step procedure ofidentifying and solving problems. You will solve problems, think critically, analyzedata, find answers, and formulate research problems or questions.After having thoroughly researched your question,you should have some educated guess about howthings work. This educated guess about the answerto your question is called the hypothesis.The hypothesis must be worded so that it can betested in your experiment. Do this by expressing thehypothesis using your independent variable (thevariable you change during your experiment) andyour dependent variable (the variable you observe-changes in the dependent variable depend on changes in the independent variable).In fact, many hypotheses are stated exactly like this: "If a particular independentvariable is changed, then there is also a change in a certain dependent variable."  "If I open the faucet [faucet opening size is the independent variable], then it will increase the flow of water [flow of water is the dependent variable].  "Raising the temperature of a cup of water [temperature is the independent variable] will increase the amount of sugar that dissolves [the amount of sugar is the dependent variable]."  "If a plant receives fertilizer [having fertilizer is the independent variable], then it will grow to be bigger than a 7
  8. 8. plant that does not receive fertilizer [plant size is the dependent variable]."  "If I put fenders on a bicycle [having fenders is the independent variable], then they will keep the rider dry when riding through puddles [the dependent variable is how much water splashes on the rider]."Notice that in each of the examples it will be easy to measure the independentvariables. This is another important characteristic of a good hypothesis. If we canreadily measure the variables in the hypothesis, then we say that the hypothesis istestable.Not every question can be answered by the scientific method. The hypothesis is thekey. If you can state your question as a testable hypothesis, then you can use thescientific method to obtain an answer.Activity 1.1Directions: Interview at least 20 adult individuals who have children in your localityand ask the question listed below.What is the most common ailment of children in your Check the age Totalcommunity? bracket 0-3 4-6 7- 10- 9 11 a. Athletes foot b. Boils c. Chicken pox d. Cold e. Constipation f. Cough g. Diarrhea h. Fever i. Measles j. Mump k. Worm l. Other / pls. specifyGuide Questions 1. What is the most common ailment in your locality? ____________________________________________________________ 2. What particular age bracket of the children mostly suffers from this ailment? 3. State the major health problem of the children in your locality? ______________________________________________________________ ____________________________________________________________ 8
  9. 9. 4. Write you hypothesis. ______________________________________________________________ _____________________________________________________________Activity 1.2Identify the problem in the picture below and make your own hypothesis. Problem: ________________________________________________________ Hypothesis: ________________________________________________________ ________________________________________________________ Problem: ______________________________________________________ Hypothesis: ______________________________________________________ ______________________________________________________ ______________________________________________________ Problem: _______________________________________________________ Hypothesis: ________________________________________________________ ________________________________________________________ Problem:________________________________________________ Hypothesis:_________________________________________________ ___________________________________________________________ 9
  10. 10. Lesson 2 - Planning Investigation, Experimentation and Data AnalysisAfter identifying and formulating the problem, you have to think carefully about theplan of the research that would test your hypothesis. In this process, you shouldconsider the options you have about different ways in which the research topic canbe investigated, that is a research design.You should try to choose a design that will give mostdefinitive answers about the research topic. But youhave to weigh this against the possibility of doing thestudy. You have to consider, among other things,your own capabilities, the availability of material orsubjects for the research, and the availability ofresources.After deciding on a research design that isappropriate to deal with the research topic and that is achievable, you have to lookagain at the broad research topic, define and refine it.For many studies, this will involve generating a research hypothesis that can betested through experimentation.Experimentation is the step in the scientific method that helps people decidebetween two or more competing explanations – or hypotheses. These hypothesessuggest reasons to explain a phenomenon, or predict the results of an action. An example might be the hypothesis that "if I let go of this ball, it will fall to the floor": this suggestion can then be tested by carrying out the experiment of letting go of the ball, and observing the results.Once hypotheses are defined, an experiment can be carried out - and the resultsanalyzed - in order to confirm, refute, or define the accuracy of the hypotheses.Listed below are the scientific processes that you could use as you try to discoverthe reliability of your hypothesis.A. Observing and Collecting Data Our understanding of the world around us is based on observations. Observing isthe use of one or more of the five senses to perceive objects or events. For example,you will use your sense of sight to observe any turbidity changes in your aquarium. Scientists also use a variety of tools to aid in makingobservations. In these experiments you will be using tools such as ahydrometer to test fluid density, as well as a variety of water qualitytest kits which will be used to monitor such factors as nitrates,phosphates and dissolved oxygen levels in your tank. 10
  11. 11. While making observations, scientists often collect data. Collecting data is the gathering and recording of specific information based on observations. You will be recording and sharing your aquarium observations with your class mates and students conducting this experiment at other schools.B. Measuring Observations are most useful when they involve quantitative data --- data that can be measured in numbers. Measuring is the process of determining the dimensions of an object, the number of objects in a group, the duration of an event, or other characteristics in precise units.C. Organizing Data Data are of little use unless they are organized. Organizing data involves placing observation and measurements in some kind of logical order such as in a graph, chart, table, or a map. This is an essential part of the Scientific Process which assists in the interpretation of the data.D. Hypothesizing Hypothesizing is the process of formulating testable statements about observable phenomena. This is often one of the first steps in a scientific investigation. A statement is testable if evidence can be collected that either supports the hypothesis or refutes it.E. Predicting To test a hypothesis, a scientist usually makes a prediction that follows from the hypothesis. Predicting is stating in advance the results that will be obtained from testing a hypothesis. A prediction can take the form of an “if - then” statement.F. Experimenting Some hypotheses or predictions can best be tested through careful observations in a natural setting, such as a field study. Others can be tested through experiments. Experimenting is the process of testing a hypothesis or prediction by carrying out data- gathering procedures under controlled conditions.G. Analyzing Data After a scientist has collected and organized data from a field study or an experiment, the data must be analyzed. Analyzing data is the process of determining whether or not the set of data is reliable and whether or not it 11
  12. 12. supports a given prediction or hypothesis. Scientists analyze data in many ways, including using statistics, interpreting graphs, determining relationships between variables, comparing the data to those obtained from other studies, and determining possible sources of experimental error.H. Inferring Inferring is the process of drawing conclusions on the basis of facts or premises instead of direct perception. Facts might include data gathered during a field study or an experiment. Premises might include conclusions drawn from previous knowledge or from past experience.I. Modeling Modeling involves constructing a representation of an object, a system, or a process that helps show relationships between data. A model may be visual, verbal, or mathematical. A biologist might create a mathematical model to show how environmental factors, such as sunlight, temperature, rainfall, and humidity, affect the growth of plants in the rain forest. Scientist sometimes uses models to help generate new predictions or hypotheses. J. Communicating Scientist does not work in isolation. Often they work in groups. In many cases they publish results of their experiments in scientific journals or present them at scientific meetings. Sharing information, or communicating, is essential to progress in science. Communication allows scientists to build on the work of others.Activity 2.1Perform the following activities:A. Go out and look for a place where you can find different kinds of leaves. 1. Use your senses in observing the leaves of at least f plants. 2. Record your observations in the table below. Leaf Color Shape Texture Odor A B C D E 12
  13. 13. Guide Questions:Answer the questions below using the data you gathered during the investigation. 1. Which of your senses gave the most information about the leaves? _____________________________________________________ 2. Which of your senses helped you the most in distinguishing the leaf samples? _________________________________________________________ 3. Your personal observation has limitations. Name several scientific instruments that may help you overcome the limitations of your senses whenever you make observations. a. Sight: _____________________________________________ b. Smell:_____________________________________________ c. Taste:_____________________________________________ d. Touch:_____________________________________________ 4. Is it important that a scientist record his data immediately? Why or why not? ______________________________________________________________ ______________________________________________________________ ____________________________________________________________B. Do the following using a thermometer Pour 500 mL water in the kettle and heat it for 20 minutes. Record the temperature every two minutes using thermometer. Graph the data with the temperature on Y-axis and the time interval on the X-axis. 35 40 45 50 Temperatures in degree Celsius 20 25 30 15 10 5 5 10 15 20 25 30 35 40 45 50 55 60 Time interval in minutes 13
  14. 14. Can you use the graph to know what will be the temperature in the next 20 minutes?Why or why not?_________________________________________________________________________________________________________________________________________________________________________________________________________C. Do the following using five textbooks and a ruler: 1. Measure the thickness of each textbook in millimeters. Do not include the cover. 2. Count the number of pages in each of the five textbooks. 3. Record you data in the table below Textbook Thickness Pages A B C D E 4. Plot the data on the graph. 35 40 45 50 Thickness in millimeter 20 25 30 15 10 5 5 10 15 20 25 30 35 40 45 50 55 60 Number of Pages 5. What are the different science processes demonstrated in the activities performed? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 14
  15. 15. Lesson 3 - Making Conclusions and RecommendationsSuppose you see a test tube filled with a clear liquid on top of a table in thelaboratory. It would be extremely dangerous and perhaps fatal to "jump to theconclusion" that it was water. There are lots of clear liquids that look like water - andmany of them are extremely dangerous. "It is a clear liquid" is an observation, but "Itis water" is not! We could perform physical and chemical tests on the clear liquid from which we might conclude - decide based on observations - that it is water, but the statement "It is water" is a conclusion - not an observation. It is a vital part of science to draw conclusions based on the data gathered from you observations. In every experiment, we collect data (observations), but the goal of the experiment is to reach a conclusion based on the data.In drawing a conclusion, identify one key source of experimental error that tookplace. Explain how it affected the results. For instance, when the wind that passedby reduced the temperature of reactants and therefore made the reaction slowerthan expected.One of the most important steps in scientific method is choosing a solution to theoriginal problem. Recommendations for the problem can be made after all thenecessary data have been gathered and analyzed.Activity 3.1Perform the following activity: 1. You are going to heat the aluminum can with an alcohol lamp, but before doing so, formulate your hypothesis. Write as many as you can. ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 2. Provide the following materials:  empty aluminum can (soft drinks can)  soft plastic bag  rubber band  alcohol lamp or candle 3. Assemble the materials:  Place the soft plastic on the lid of the aluminum can.  Wrap it around the lid with a rubber tightly. 15
  16. 16. 4. Now heat the can for about 2 minutes. Observe what happens. Record your observations. (Be careful in heating the can. See to it that the flame will not touch the plastic.) 5. Are all your hypotheses correct? ______________________________________ 6. What conclusion can you make out of the experiment you have performed? Formulate your conclusion. ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ ______________________________________________________________As you perform this investigation, you will:  become familiar with the steps of the scientific method  use the scientific method of thinking how to solve a problem.Answer the following questions and write your answers on the space provided aftereach number.1. The first step of a scientific method is to identify the problem you wish to solve. What is the problem in this activity? ___________________________________________________________ ___________________________________________________________2. After you identify the problem, it is time to make observations. What do you see? ___________________________________________________________ ___________________________________________________________3. Next, the data from your observations must be organized. What factors do you think play a part in your observations? ___________________________________________________________ ___________________________________________________________4. Verify your answer or solution by repeating the experiment if you wish to.Activity 3.2Try the activity given in the pretest to verify the answers:Perform the experiment using the same materials, 5 coins of different sizes – 10-peso, 5-peso; 1-peso and a 25-centavo coin.Do the following procedure:  Lay the coins one by one on a table.  Get a medicine dropper 16
  17. 17.  Fill the medicine with water.  Drop the water in each coin one at a time.  Count the number of water drops needed to fill the coins. Stop dropping when the water spills over the coin.  Do the same procedure with the other coins.  Record the data on the table provided for. No. of Trials Number of Water Drops 10-peso 5 - peso 1-peso 25-centavo123AverageAnswer the following questions.1. What is the problem in this activity? _________________________________________________________________ _________________________________________________________________2. Formulate your hypothesis. (List down as many as possible. ) _________________________________________________________________ _________________________________________________________________3. Analyze your results. Which coin holds the greatest number of water drops? a. a 10-peso coin b. a 5-peso coin c. a 1-peso coin d. a 25 centavo coin4. What factor do you think has something to do with the differences in the number of water drops a coin can hold? a. distance of medicine dropper from the coin b. sizes of the coins c. diameter of the dropper d. all of the above5. Which of the following can you identify as the responding variable? a. number of water drops b. size of the coin c. diameter of the dropper d. kind of medicine dropper6. Where should you base your conclusion or generalization? a. gathered data b. results of experiment performed 17
  18. 18. c. direct observations d. what others say about it.After firming up your understanding of the scientific method, you have to deepenyour understanding by doing the following activities. DEEPEN Your UnderstandingHere, you shall be engaged in understanding scientific knowledge which includes theprocessing and making meanings out of the information. You need to reflect, revisit,revise and rethink your ideas; express your understandings and engage inmeaningful self-evaluation; and undergo in-depth exploration of scientific methodsusing multiple sources of information and various modalities of manifestations oflearning. 1. Write an essay on how scientific processes and scientific methods helped you in solving a particular problem that you encountered in your life. 2. What would you like to be in the future? How would your understanding of scientific processes and scientific methods help you in your future career? 3. Name three basic problems in your locality. Think of possible solutions to these problems applying your knowledge in scientific processes and scientific method. Problems of Procedures in Solving the Problem Locality 1. 2. 3. 18
  19. 19. Note: For more reliable data, interview at least 20 adult individuals in yourcommunity and ask what the main problems in your community are. Gather thenecessary data and identify the top three problems of the locality. 4. Explain how scientific knowledge is acquired and validated. ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 5. When do scientific methods become valuable? ______________________________________________________________ ______________________________________________________________ _____________________________________________________________Summative TestA. Directions: Choose the letter of the correct answer. 1. In what step of the Scientific Method do you ask a question? a. Conclusion b. Problem c. Hypothesis d. Information 2. In what step of the Scientific Method do you go to the library or ask an expert? a. Conclusion b. Hypothesis c. Problem d. Information 3. The possible answer to the problem. a. Hypothesis b. Conclusion c. Data d. Experiment 4. The actual answer to the problem. a. Hypothesis b. Data c. Conclusion d. Information 5. The variable that you change in the experiment. Also called the manipulated variable. a. Controlled b. Dependent c. Independent d. Responding 19
  20. 20. 6. The variable that changes because you changed the other variable. Also called the responding variable. a. Dependent b. Independent c. Controlled d. Manipulated 7. The group in the experiment that does not get the variable is called the ___________ group. a. Dependent b. Control c. Independent d. Responding 8. The variables in the experiment that do not change are called the __________ variables. a. Controlled b. Independent c. Dependent d. Manipulated 9. Recorded observations and measurements. a. Information b. Conclusion c. Hypothesis d. Data 10. The conclusion is based on the results of the _____________. a. Information b. Hypothesis c. Experiment d. ProblemB. Read the article and answer the questions below.Niko Tinbergen (1907-1988) was a Swedish Ethologist (animal behaviorist) famousfor studying animals in their native habitats. One of his classic experiments involveda bird called the black-headed gull (Larus ridibundus). Black-headed gulls build nestsof twigs on the ground and lay light brown eggs that are covered with dark brownspots. However, the inside of the egg is white in color. Tinbergen noticed that adultgulls pick up the eggshells shortly after a chick has hatched, and fly them to alocation far from the nest, where they are left. Since this behavior requiredexpending energy and time that could have been spent feeding and protecting thechicks, Tinbergen wanted to know why the birds did this.Problem: Why do black-headed gulls remove eggshells from the nest?Hypothesis: The white interior of the shell is not camouflaged and attracts predators to the nest. Therefore, the gulls remove the shells to decrease predation. 20
  21. 21. Test: Tinbergen and his co-workers collected gull eggs and painted 69 of them white and left 68 of them with their natural color. (Statistically, these numbers are close enough to be considered equal.) The researchers then scattered the eggs next to a gull breeding area and observed from a nearby blind. Predation rates were recorded for white versus natural colored eggs.Data Original Eggs Taken by Eggs Not Number of Predators Taken Eggs White Eggs 69 43 26 Natural Eggs 68 13 55 a. Do the results of this experiment support the hypothesis? Why or why not? b. If you were working with Tinbergen, what would you suggest be done next? c. Identify the experimental and dependent variables.Now that you have gained a better understanding of scientific processes andmethods, you are now ready for the next level- transferring what you have learned. TRANSFER Your Understanding This part will let you transfer your learning in new settingsand use this creatively to generate new ideas, view things differently and reengineerprocesses. You shall be involved in designing, constructing, planning, producingnew knowledge and/or inventing products which can contribute to the protection ofthe environment and sustainable use of resources.Using your data from Activity 1 # 3 from DEEPEN Your Understanding, prepare apresentation that would let you discuss your proposed solutions to the top threeproblems in your locality. With your teacher’s approval, you may make apresentation to the following groups:  Sanguniaang Kabataan officers  Barangay officials  Group of studentsYour presentation should be based on the following criteria: 1. Community-based 2. Application of Scientific Method 21
  22. 22. Congratulations!You have finished module # 1. And you are now ready to proceed to the next module. 22
  23. 23. Answer key:Pre-Assessment Summative Test 1. D 1. B 2. B 2. D 3. B 3. A 4. C 4. C 5. B 5. C 6. Interpretation 6. A 7. Observation 7. B 8. Generalization 8. A 9. Hypothesizing 9. D 10. Identifying the problem 10. CReferences/ Weblinkshttp://www.sciencebuddies.orghttp://www.clcillinois.eduhttp://www.clipartguide.com 23