 Oil Eating Bacteria #1-2  Write a response to the following prompt. Your response must be more than one sentence and it can’t include “I DON’T KNOW” (IDK) Why do we trust that Scientists have correct explanations for how things work?

Science is a way of learning about the natural world. Science also includes all the knowledge gained from exploring the natural world.

Scientists use skills such as observing, inferring, and predicting to learn more about the world.  Observing means to use your senses (sight, hearing, touch, taste, or smell) to gather information.  When you explain or interpret the things you observe, you are inferring, or making an inference.  based on prior knowledge, experiences, and observations  Predicting means making a forecast of what will happen in the future based on past experience or evidence.

 Take 5-7 minutes to read Thinking Like a Scientist. Underline or highlight any unfamiliar words. Be ready to discuss.

Successful scientists possess important attitudes such as curiosity, honesty, open-mindedness, and skepticism.  An important attitude that drives scientists is their curiosity. Successful scientists are eager to learn.  Good scientists are honest. They always report their observations and results truthfully.  Scientists need to be open-minded, or capable of accepting new and different ideas.  Open-mindedness should always be balanced by skepticism, which is having an attitude of doubt.

 Example 1 - you hear a whistling sound outside (observation) and say it is a bird (inference). Of course, it may have been a tape of a bird! Or a Space Alien!  Example 2 - you see an unusual light in the sky (observation) and say it is an Alien Spacecraft (Inference)

1. Are there cars parked on the side of the road? 2. What color is the pickup truck driving in the road? 3. Any minivans around? 4. What does the blue sign say? 5. What is the speed limit? 6. Are there any pedestrians on the road?

A means of acquiring knowledge scientifically; the system of advancing knowledge by formulating a question, collecting data about it through observation and experiment, and testing a hypothetical answer.

 Question  Research  Hypothesis  Experiment  Data analysis  Conclusion (report results)  Retest

 Observations are gathered through your senses  A scientist observes something interesting in the natural world  The scientist formulates a question

The scientist gathers information about the question through research and more observation.

 Based on his research, the scientist predicts an answer to the question  A hypothesis is sometimes called an educated guess or prediction  A hypothesis must be testable  A hypothesis is often written as an “If… Then…” statement

1. Do not use I, me, my, or they (no personal pronouns). 2. If possible, write the hypothesis in an “if-then” format. (IF this happens, THEN this will happen.) 3. Write the hypothesis as a statement, not a question. Examples: If salt is added to fresh water, then the freezing point of the water will be lower than 0°C. If a city is located near tectonic plate boundaries, then the city will experience more earthquakes.

1. Practice Question: Jared investigated chemical reactions based on smell, color change, and release of bubbles. What type of evidence would support any conclusion Jared makes A.a measurement B.an observation C.a calculator D.an estimation 2.Scientific Question: Are elephants afraid of mice? 3. Hypothesis: Write a hypothesis predicting your answer.

An experiment is a procedure (usually written in steps) that will prove or disprove the hypothesis by carefully using a controlled process.

Variable – Any factor in the experiment that can change

An experiment is good or “valid” if the scientist changes only ONE variable at a time!

The scientist changes one variable and then observes or measures what happens as a result.

The variable that is purposefully changed in the experiment is called the independent variable. (should only be one thing)

The variable that responds to the change is called the dependent variable. This is what is being measured in the experiment.

All other variables must be kept exactly the same so that they will not affect the outcome of the experiment. These are called control variables. They are used for comparison.

In your hypothesis:  the “if” statement explains how the independent variable will be changed.  the “then” statement explains how the dependent variable will most likely respond.  If the independent variable changes, then the dependent variable will change.

An experiment was done to see if rotted leaves added to soil had an effect on tomato production. One tomato plant was grown in each of four large tubs. The following amounts of rotted leaves were added to the tubs: Tub A had 15 kg added, Tub B had 10 kg added, Tub C had 5 kg added, and Tub D had no rotted leaves added. Each tub had the same type and amount of soil, got the same amount of sunlight, and was watered the same amount. The total mass (in kg) of tomatoes produced by each plant was measured and recorded for three months. What is the scientific question? Does adding rotted leaves to soil increase tomato production? What is a possible hypothesis? If rotted leaves are added to soil, then tomato plants will produce a larger mass of tomatoes.

An experiment was done to see if rotted leaves added to soil had an effect on tomato production. One tomato plant was grown in each of four large tubs. The following amounts of rotted leaves were added to the tubs: Tub A had 15 kg added, Tub B had 10 kg added, Tub C had 5 kg added, and Tub D had no rotted leaves added. Each tub had the same type and amount of soil, got the same amount of sunlight, and was watered the same amount. The total mass (in kg) of tomatoes produced by each plant was measured and recorded for three months. What is the independent variable?The rotted leaves What is the dependent variable? The total mass of tomatoes produced by each plant What are the control variables?Type and amount of soil, amount of sunlight, amount of water, time

James wondered if music had an effect on plant growth. To answer the question, he placed 25 bean plants into each of two identical greenhouses. He played music constantly in one greenhouse and not at all in the other greenhouse. The greenhouses were kept at the same temperature, and all plants received the same amount of sunlight, fertilizer, and water. At the end of two weeks, the height of all the plants was measured. What is the scientific question? What is a possible hypothesis? What is the independent variable? What is the dependent variable? What are the control variables?

 Data - Facts, figures, and other observations gathered during an experiment; often organized into tables or graphs  Quantitative data comes from observations that can be measured in numbers or amounts (length, time, mass, temperature, etc.)  Qualitative data comes from observations that can’t be measured (color, shape, taste, etc.)  Both types of data are important to scientists!

For extra practice! Qualitative vs. Quantitative Data GEBRA/AD1/qualquant.htm ad1/dataprac.htm

 A summary of what was learned based on the data obtained during the experiment. It should answer the scientific question.  The conclusion may: support the hypothesis (accept) or prove it to be false (reject)

In order to verify the results, experiments must be REPEATED!

1)Ask a Scientific Question 2) Make Observations and do Research about the question 3) Form a Hypothesis predicting the answer (if…then…) 4) Design an Experiment to test the hypothesis 5) Collect and analyze Data 6) Form a Conclusion 7) Retest

 English System – the US is the only industrialized nation that uses this system as its standard measurement. (pounds, ounces/cups, miles, Fahrenheit, etc.)  History – was based off of body parts and commonly used objects.  Drawbacks: complex converting and same names for different measurements such as ounce for both weight and liquid capacity.

 Metric (International System of Units SI) universally used in scientific work, and widely used around the world for personal and commercial purposes.  A standard set of prefixes in powers of ten may be used to derive larger and smaller units from the base units.

1. Practice Question: Ethan investigated which of three liquids had the highest boiling point. He put equal amounts of liquid in different beakers and placed each beaker over the same amount of heat. To compare the liquids’ boiling points, he measured how long it took for each liquid to boil. The following table shows his results. Amount of Time for Liquid to Boil Ethan concluded that Liquid B had the highest boiling point. Which of these led to this conclusion? A. Quantitative measurement of how hot the liquids got B. Qualitative observation of how long it took for the liquids to boil C. Quantitative measurement of how long it took for the liquids to boil D. Qualitative observation of how hot the liquids got 2. Writing Prompt: Write the instructions for fixing a peanut butter and jelly sandwich. LiquidTime (in seconds) A94 B230 C196

Mass – unit is grams (g); used for measuring the amount of matter in an object. Tools used: triple beam balance, digital balance Triple beam balance Digital balance

 Unit is cm 3 or m 3  used for measuring the amount of space a solid object takes up.  To find the volume of a regular solid measure the length, width, and height. Multiply all 3 numbers together.  To find the volume of an irregular solid – use the water displacement method (one mL equals 1 cm 3 )  Ruler, graduated cylinder and water

 Unit – liter (L) (in class use mainly mL)  Used to measure how much space a liquid takes up.  Tools: graduated cylinders (most accurate), beakers, flasks beaker graduated cylinder flask

 Unit – meters (m)  Used for measuring the distance between two points.  Tools - rulers/meter sticks

 Unit – Celsius (C); Celsius is based on the freezing and boiling point of water (0° degrees for freezing and 100° degrees for boiling). Fahrenheit is less accurate.  Used to measure the movement of molecules in a substance. The faster the molecules are moving, the higher the temperature.  Tool: Thermometer

 The amount of matter in a given volume  Density = Mass (g)/ volume (cm 3 ) D = M/V  Practice Problems: 1. Rock A has a volume of 15cm 3 and a mass of 45 g. What is its density? 2. Rock B has a volume of 30cm 3 and a mass of 60g. What is its density? 3. Which rock is heavier? Which rock is more dense?

A golden-colored cube is handed to you. The person wants you to buy it for $100, saying that is solid gold. You pull out your old geology textbook and look up gold in the mineral table, and read that its density is 19.3 g/cm 3. You measure the cube and find that it is 2 cm on each side, and weighs 40 g.  What is its density?  Is it real gold?  Should you buy it?

1. How much matter in a calculator? 2. How much space dr. pepper takes up in your drinking cup? 3. How much space a textbook takes up in your book bag? 4. The distance from Main Hall to Math Hall? 5. How much space a paper clip takes up? 6. The height of your desk?

1. How much matter in a calculator? use a balance and measure in grams 2. How much space dr. pepper takes up in your drinking cup? use a graduated cylinder and measure in milliliters (mL) 3. How much space a textbook takes up in your book bag? use a ruler, LxWxH, unit cm 3 4. The distance from Main Hall to Math Hall? ruler, meters 5. How much space a paper clip takes up? water displacement method, cm 3 6. The height of the your desk? ruler, centimeters (cm)

7. A scientist suspects that the amount of Vitamin A in the diet of female mice affects the number of offspring born. To test this idea, the scientist adds extra Vitamin A to the food of 50 female mice for a period of two months. Another group of 50 female mice gets no vitamin supplements. Each mouse in the study is the same species, gets the same amount of food and daily exercise, and is kept at the same temperature. At the end of two months, the total number of offspring are counted and recorded for each group. Which of the following is the best hypothesis? Explain why the wrong ones are incorrect. A. Female mice will eat more Vitamin A if they have more offspring. B. If female mice are given Vitamin A, then the number of offspring will increase. C. If you give mice Vitamin A, then they will have more offspring. D. I think the offspring number will increase if the mice are given Vitamin A.