Presentation on theme: "Course Semester Pretest"— Presentation transcript:
1 Course Semester Pretest Today you will take the semester course pretest. This is what you will be tested on at the end of semester test (midterm) in January.Again, this is for my instructional purposes to decipher what you are already proficient in. It will be entered in eSembler but with a 0% weight so it will NOT count against you.Don’t forget to turn in your signed syllabusDuplicate questions - #4 & 15 and #14 and 20
2 Opening AssignmentHow is science different from other fields of study like history, art, and philosophy?List the steps of the scientific method.
3 Unit 1 Nature and process of Scientific Investigations By Mrs. Shaw
4 UNIT 1 - Part 1 Learning Goals Students will be able toDifferentiate the study of science from other fields of study like history, math, and english.Explain the process of scientific investigations.
5 What is science?At it's most fundamental level we can define science as two different activities:the methodical collection of facts about the universethe attempt to create explanations of how those facts relate to each otherThe "collection of data" part of science is pretty easy to understand, but the "tie it all together" part is widely misunderstood.
6 Science VS. Other fields of study Science is evidence based explanations of the physical and natural world!!Science is a dynamic (always changing), self- correcting process. What was true once, becomes false or modified with more study and testing.In the field of science, there are three words in rising order of importance: conjecture, hypothesis and theory.
7 Conjecture, Hypothesis, and Theory A conjecture is an interesting idea about the universe, but it's little more than speculation; comes from a persons memory, no research has been done.A hypothesis is a prediction of what you expect to happen and why; it means that someone has thoroughly researched the topic and hasn't found any contradictions.A theory is backed by dozens or hundreds of people, who have examined every possible aspect of the theory they can, and have accumulated a very large body of evidence to back it up. A theory is as close to scientific fact as you can get.
8 Check for Understanding #1 Our current ideas on how tectonic plates move and have moved over time is based on a significant amount of empirical (verifiable) evidence by qualified scientists who have studied this idea.Is this a conjecture, hypothesis, or a theory?
9 Check for Understanding #2 Mark noticed that all the plants in his house were angled toward the windows as they grew.He made a statement that “Plants must be attracted to sunlight”.Is this a conjecture, hypothesis, or a theory?
10 Check for understanding #3 Mark decided to do some research and he found 10 different valid sources where scientists did studies that showed that plants will grow towards sunlight as a survival characteristic known as phototropism.Mark made a prediction based on his research:“If a plant is placed in a box with a hole cut into the corner of the top, then the plant will grow towards that opening because plants have survival characteristics known as phototropism where they will seek sunlight to help them create their own food.”Is this a conjecture, hypothesis, or a theory?
11 Scientific MethodThere is not one standard scientific method, however there is a generally agreed upon model that describes how science operates.1. State the problem/question/observation2. Research the problem3. Form a hypothesis4. Test the hypothesis (experiment)5. Record and analyze data6. State the conclusion (publish)7. Repeat the work to validate
12 Scientific Method: Step 1 State the problem:•What is the problem? (ask yourself)•The problem is a scientific question that can be answered by experimentation.•Should be stated in very clear, precise terms.•Should not be too broad.•This is typically stated in a question format•EXAMPLE: Will taking one aspirin per day for 60 days decrease blood pressure in females ages 12-14?
13 Scientific Method: Step 2 Research the problem: Has anyone ever tested this question before . . .if yes, what were their results?•The researcher will typically gather information on the problem. They may read accounts and journals on the subject, or be involved in communications with other scientists•Scientists build on the work of previous researchers. The first step is to do a literature review to find out what previous research has already been done in the field.•EXAMPLE: Some people relate stories to doctors that they feel relief from high blood pressure after taking one aspirin per day. The idea is not scientific if it is untested or if one person reports this (called anecdotal evidence).
14 Scientific Method: Step 3 Form a hypothesis, or probable solution, to your problem:•Hypothesis - a testable explanation about how a change in the independent variable will affect the dependent variable stated in a way that is testable.•An explanation of a cause and effect relationship•Ideally this should be written in an if-then format.•EXAMPLE: If a female aged takes one aspirin per day for 60 days, then her blood pressure will decrease.
15 Step 3 ContinuedA statement is testable if evidence can be collected that does/does not support it.•Must be falsifiable•A hypothesis cannot be proven true beyond all doubt because new data may be introduced.•It is impossible to test all given conditions, and someone with more knowledge, sometime in the future, may find a condition under which the hypothesis does not hold true.
16 Check for Understanding #1 Mom and I were baking a cake for my sister’s birthday. We didn’t have any baking powder. The recipe said to add one teaspoon of baking powder to the cake batter. Since it was such a small amount we baked the cake anyway without the baking powder. We were very disappointed when the cake came out of the oven flat instead of fluffy.Problem question:Research:Hypothesis:
17 Check for Understanding #1 Mom and I were baking a cake for my sister’s birthday. We didn’t have any baking powder. The recipe said to add one teaspoon of baking powder to the cake batter. Since it was such a small amount we baked the cake anyway without the baking powder. We were very disappointed when the cake came out of the oven flat instead of fluffy.Problem question: Does baking powder in cakes cause it to rise?Research: the effect of baking powder in cakesHypothesis: If baking powder is added to cake batter then it will rise because baking powder in cakes cause a chemical reaction to occur that releases gas that push the cake up..
18 Check for Understanding #2 Mr. Krabbs wants to make Bikini Bottoms a nicer place to live. He has created a new sauce that he thinks will reduce the production of body gas associated with eating crabby patties from the Krusty Krab.Problem question:Research:Hypothesis:
19 Check for Understanding #2 Mr. Krabbs wants to make Bikini Bottoms a nicer place to live. He has created a new sauce that hethinks will reduce the production of body gas associated with eating crabby patties from the Krusty Krab.Problem question: Does Mr. Krabbs sauce work to decrease gas?Research: Did the new sauce help reduce Mr. Krabbs gas? What is the active ingredient?Hypothesis: If 20 people at the Krusty Krab are given Mr. Krabbs new sauce, then they will experience less gas because
20 Check for Understanding #3 Indian River Lagoon has seen an overgrowth of toxic algae blooms over the past few years. During this same time period, there have been increases in the amount of water being discharged from Lake Okeechobee into the Indian River Lagoon.Problem question:Research:Hypothesis:
21 Scientific Method: Step 4 Test your hypothesis:•Perform a controlled experiment: an organized series of steps used to test a hypothesis by comparing a control group to the experimental group.•All variables are controlled (kept constant) except the one factor (the independent variable) that is being changed.•Should be detailed, clear and planned step by step so the experiment can be replicated by other scientists in the future•Investigation of a cause and effect relationship between the independent variable and the dependent variable.•EXAMPLE: Test 100 females, ages 12-14, to see if taking one aspirin a day for 60 days lowers blood pressure in those females.
22 STEP 4 ContinuedVariable: Any factor in an experiment that changes or could be changed.•Only one variable is isolated and tested while all other variables are held constant.•Independent Variable (I.V.): The variable changed, on purpose, in the experiment by the researcher.•EXAMPLE: Taking an aspirin or not. This is what the experimenter changes between this groups in the experiment.•Dependent Variable (D.V.): The variable that may respond to the I.V. and is being measured in the experiment.•EXAMPLE: The blood pressure of the individuals in the experiment, which may change from the administration of aspirin.
23 STEP 4 ContinuedConstants (controlled variables): conditions that remain the same in the experiment•A factor in an experiment that is kept the same in all trials•EXAMPLE: Some probable constants would include: only females were used, only females between ages 12-14, the same dosage of aspirin was given to all the individuals in the experimental group for the same defined time interval –60 days, the same brand of aspirin was given, the same type of diet was ideally given to the members of both groups as well as the same activity level prescribed.
24 Step 4 ContinuedControl or Control Group: The group, or experimental subject, which does not receive the Independent Variable or a change in the Independent Variable•The standard for comparison in an experiment; the independent variable is not applied to the control group, or is not changed in the control group.•EXAMPLE: the group of females that does not get the dose of aspirin.•Experimental Group: The group, or experimental subject, which does receive the Independent Variable, or a change in the Independent Variable.•The test group
25 Opening AssignmentGet your homework out and ready to review. Then work on question below.Differentiate between the followingA dependent and an independent variableA control group and an experimental groupFire drill procedure review
26 Step 4 Continued Put it all together… •All the groups in an experiment are treated exactly the same except for the manipulated (independent) variable. In the experimental group, the manipulated variable is being added or changed. The control group is used as a standard of comparison. It may consist of objects that are not changed in any way (not getting the independent variable) or objects that are being treated in the “usual” way (no change in the independent variable)•If the __________________ ________________________,Independent variable Describe how it will be changedthen the _______________ will _______________________.Dependent variable Describe the effect
27 Step 4 ContinuedBy controlling the variables and only changing one at a time (I.V.) researchers are able to conclude that the changes in the dependent variable are due exclusively to changes in the independent variable.•If the expected results are obtained, then the hypothesis is supported (not proven).•If the expected results are not obtained, then the hypothesis is rejected or refuted•No matter the outcome, a tested hypothesis has value in science because it helps researchers advance scientific knowledge.
28 Scientific Method: Step 5 Recording and analyzing the data:•What sort of results did you get?•Data are recordings of information observed.•Data can be qualitative or quantitative•Data is typically organized into data tables.•The data is then graphed for ease of understanding and visual appeal.•EXAMPLE: Out of 100 females, ages yrs., 76 had lower blood pressure readings after taking one aspirin per day for 60 days.
29 Review of Qualitative vs. quantitative observations and data Qualitative: Observations that are made using your 5 senses – hear, see, touch, smell, taste. These observations can be subjective – which means they may vary based on the person’s individual experience.Quantitative: Observations that are made based on numbers – counting, measuring, etc. These observations are much more objective and therefore valid in science.
30 Step 5 ContinuedWhen data does not support a hypothesis it is rejected•Data is still useful because provides information and may lead to a new hypothesis•When data does support a hypothesis we say it “supports the hypothesis” or provides evidence in favor of the hypothesis but we do not say that it proves the hypothesis•A hypothesis is never proven beyond all doubt because new data may be introduced
31 Scientific Method: Step 6 Stating the conclusion:•What does all the data mean?•Based on whether the results support or refute the hypothesis, researchers review the relationships among the data and make a final statement summing up the results of the experiment.•Does the data support your hypothesis?•EXAMPLE: The data shows that taking one aspirin per day for 60 days decreases blood pressure in 76% of the tested females ages compared to a decrease in blood pressure in 11% of the control group. Therefore, the original hypothesis has been supported, that taking one aspirin per day can decrease blood pressure.9
32 Check for Understanding #1 During a scientific investigation, which step will a scientist perform first?A.Collect and organize data.B.Plan the experimental procedure.C.Make observations and then define the problem for investigation.D.Defend conclusions drawn from data.
33 Check for Understanding #2 Ellis’s class is studying tide pools and starfish. Which of the following is an example of a hypothesis she might make?A. The starfish population of tide pools varies.B. Atlantic tide pools have more starfish than Pacific tide pools do.C. The water temperature of tide pools is increasing.D. If the water temperature in the tide pool increases, then the starfish population will decrease because starfish require a specific water temperature of degrees to maintain homeostasis.
34 Check for Understanding #3 Chemists classify some substances as acids. Vinegar is an acid that is often used during cooking to flavor or to preserve foods. Which property of vinegar can you observe qualitatively? A. It has a pH of 4.25 B. Based on the pH scale it is considered to be a moderately strong acid. C. Vinegar is very reactive when it is exposed to baking soda.
35 Practice ScenarioHomer notices that his shower is covered in a strange green slime. His friend Barney tells him that coconut juice will get rid of the green slime. Homer decides to check this this out by spraying half of the shower with coconut juice. He sprays the other half of the shower with water. After 3 days of "treatment" there is no change in the appearance of the green slime on either side of the shower.What is Homer’s question?What would his hypothesis be? If then becauseWhat should Homer write for his conclusion?
36 Review of the scientific method MLHW1wU8dINow: List 3 qualitative and 3 quantitative observations you can make about IRCHS. Make 3 questions that you would like to see tested.
37 What are Variables?A variable is any factor that can be controlled or changed in an experiment. There are 3 types of variables:Dependent: the variable that is measured or observed for a responseIndependent: the variable that you change in the experiment – remember there can only be one!Controlled or constant: the variable that does not change during the experiment
38 Check for understanding #1 Variables Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, Smithers counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks.Identify the:1. Control Group2. Independent Variable3. Dependent Variable4. What should Smithers' conclusion be?
39 Check for understanding #1 Variables Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, Smithers counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks.Identify the:1. Control Group – Group B because it is not given juice2. Independent Variable – amount of juice given3. Dependent Variable – amount of stacks stapled4. What should Smithers' conclusion be? Group B made more stacks and they did not receive the juice so hishyopthesis is not supported.
40 Controls and Variables Practice worksheet Work together with your table partner to analyze the scenarios and determine the variables. Please raise your hand if you have any questions.
41 Opening AssignmentGet your homework out so I can check it and we can go over it. . . Then read the scenario below and answer the following questions.Sponge Bob notices that his pal Gary is suffering from slimotosis, which occurs when the shell develops a nasty slime and gives off a horrible odor. His friend Patrick tells him that rubbing seaweedon the shell is the perfect cure, while Sandy says that drinking Dr. Kelp will be a better cure. Sponge Bob decides to test this cure by rubbing Gary with seaweed for 1 week and having him drink Dr. Kelp.After a week of treatment, the slime is gone and Gary’s shell smells better.What was the initial observation?What is Sponge Bob’s hypothesis? (a cause / effect relationship stated in an “If. . .then, because” format)What is the independent variable?What is the dependent variable?What should Sponge Bob’s conclusion be?
42 Scientific Theories Scientific Theories are evidence based explanations of why things happen in nature.represent the most powerful explanation scientists have to offer.rarely totally discarded, more frequently they are modified as new evidence is discovered.CANNOT turn in to a scientific law.
43 Scientific Laws Scientific Laws are generalized rules to explain a body of observationsusually in the form of a verbal or mathematical statement.imply a cause and effect between the observed elementsdo not attempt to explain “why” but rather just state “what” will happen.
44 Commonalities between a scientific law and theory: •Both are based on tested hypotheses•Both are supported by a large body of empirical data(verifiable evidence!!)•Both help unify a particular field•Both are widely accepted by the vast majority of scientists within a discipline•Both could be shown wrong at some time if there are data to suggest so
45 UNIT 1 – Part 3 Data Analysis and Graphing Learning Goals Students will be able to:Identify the mean, median, mode, and range in a specific set of dataCreate an appropriate graph to document and analyze a set of data
46 Data Analysis Mean (a.k.a. average) Median (a.k.a. middle) Total sum of all numbers (data) divided by the number of observationsMedian (a.k.a. middle)Rank all numbers (data) from lowest to highest, the median is the number in the middleIf there is an even number of data then average the two middle numbers to calculate the medianMode (a.k.a. most)The number (data) that occurs most frequentlyRangeThe difference between the largest and the smallest values
47 Practice A scientist studying the density of fiddler crabs on various shorelines collects the following data. Copy the sets of data and then calculate the mean, median and mode for each location.Location A Location B Location C
48 Check your answers Mean Median Mode Location A Location B Location C What would the range be for each set?
49 Why do we Graph Data in Science? We graph data in science to show patterns and trends.A picture is worth a thousand words!
50 Review of Types of data (information) Variableswhat you measure in an experimentdependent variablemeasured variableunpredictable change: we don’t know how it will change until we do the experimentY-axisindependent variablemanipulated variablepredictable change: it only changes because we chose how it would changeX-axisThe effect of _____________ on _____________INDEPENDENTDEPENDENT
51 Examples of experiments 1 How does fertilizer affect the growth rate of plants?we set up an experiment testing different amounts of fertilizer on different plants & measuring the growth (height) of the plants:dependent variable (Y-axis)?height of plantsindependent variable (X-axis)?amount of fertilizerThe effect of _____________ on _____________Amount of FertilizerHeight of Plants
52 Examples of experiments 2 How does exercise affect heart rate of 10th grade student?we set up an experiment testing different lengths of time of exercise (minutes) on the heart rate of students:dependent variable (Y-axis)?heart rateindependent variable (X-axis)?minutes of exerciseThe effect of _____________ on _____________ExerciseHeart Rate
53 Examples of experiments 3 What’s the favorite drink of students?we set up an experiment surveying students and asking which is their favorite drink :dependent variable (Y-axis)?number of studentsindependent variable (X-axis)?type of drinkThe effect of _____________ on _____________Type of DrinkHow many students chose it
54 Making pictures out of data Graphsline graphsgraphing data that shows continuous changebar graphs (or histograms)graphing data that is in disconnected groupsHow’s a critter to choose?
55 elevation (feet above sea level) How does elevation affect temperature?Line graph!elevation (feet above sea level)temp.(°C)30500251000201500152000102500530252018temperature15101200 ft?550010001200150020002500elevation
56 Which drink do you like best? numberCoke1PepsiWater4Iced teaGatorade36Bar graph!54number of students32Red Bull?1CokeRBPepsiRBwaterteaGatoradetype of drink
57 Practice with Graphing Create an appropriate graph using the data that you copied earlier. Don’t forget you want to graph the mean only.
58 UNIT 1: Part 4 Design and Conducting a group experiment - Learning Goals Students will be able to design and conduct a group experiment.
59 Opening AssignmentCreate a Venn diagram to compare and contrast scientific theories and scientific laws.Scientific theoriesScientific Laws
60 Marshmellow Flight Experiment Read the directions to perform the “Marshmallow Flight” experiment.
61 Opening AssignmentPractice designing an experiment: Design an experiment based on the scenario below. Remember to list the question, hypothesis, variables, and procedures.Lisa is working on a science project. Her task is to answer the question: "Does Rogooti (which is a commercial hair product) affect the speed of hair growth". Her family is willing to volunteer for the experiment.
62 Heart rate and Exercise challenge Design an experiment to test a question relating to these two variables; heart rate and exercise.Perform the experiment Collect your data, analyze it, graph itForm a conclusion.
63 Opening AssignmentList 3 “problems” with the experiment you designed yesterday.Create an experiment to test the question“Does Coke or Diet Coke produce a higher geyser when Mentos are added?Hypothesis:Variables:Procedure:
64 the Mentos and Coke Challenge Coke vs. Diet Coke Question: “Does Coke or Diet Coke produce a higher geyser when Mentos are added?Hypothesis: If regular Coke and Diet Coke are combined with mint Mentos, then the Diet Coke will produce a higher geyser becauseVariables:Dependent: the height of the geyserIndependent: the type of Coke (regular or diet)Constants: same amount and type of Mentos, same environmental conditions, same temperature of the soda, same amount of the soda
65 The Scientific Method In Action Copy the questions below in your notebook.1. What warnings do they give to viewers at the beginning of the show?2. What myth or legend are they investigating? Pick one if there are more than one in the clip you are viewing.3. What did they know before they began investigating?4. What did they do to investigate the myth/legend?5.What did they learn from their investigation - confirmed or busted? Why?6. Identify any controls and variables involved in the investigation.7. Identify the safety measures they used to prevent accidents and/or injuries.8. Are their results reliable? Explain.
66 Opening Assignment Practice Graphing An environmental scientist did a study to answer the question: Does the pH of the water affect the density of the tadpoles in the Indian River Lagoon. Copy the chart below, create a graph, and answer the questionsA. Make a line graph of the data.B. What is the dependent variable?C. What is the independent variable?D. What is the average number of tadpoles collected per sample?E. What is the optimum water pH for tadpole development?F. Between what two pH readings is there the greatest change in tadpolenumber?G. How many tadpoles would we expect to find in water with a pH reading of 5.0?
67 More practice A. Ethylene is a plant hormone that causes fruit to mature. The data aboveconcerns the amount of time it takes for fruit to mature from the time ofthe first application of ethylene by spraying a field of trees.B. Make a line graph of the data.C. Make a key for the different kinds of apples being graphed.D. What is the dependent variable?E. What is the independent variable?