Lesson 1.2 The Nature of Science The word science comes from the Latin word scientia, meaning “knowledge.” 1

What Science Is and Is Not Lesson 1.2 The Nature of Science What Science Is and Is Not organized way of studying the natural world knowledge gained from such studies. relies on evidence from measurements and observations. Scientific ideas -“supported,” not “proven” 2

The Process of Science Science involves: -asking questions Lesson 1.2 The Nature of Science The Process of Science Science involves: -asking questions making observations seeking evidence -sharing ideas analyzing results. 3

Lesson 1.2 The Nature of Science Observations . made with the eye, instruments, reading scientific literature. happen unexpectedly or be planned. lead to questions Use Models 4

Lesson 1.2 The Nature of Science Hypotheses attempt to answer questions by devising hypotheses—testable ideas. If/Then statements Explain a phenomenon or answer a scientific question Generate predictions (prediction is expected observation if the hypothesis is true.) Can be supported or rejected by data If rejected -new hypotheses formed 5

Experiments Activity designed test the validity of a prediction or hypothesis . Controlled Study: 2 parts to an Experiment: A. Control group- has only the controlled variables. (comparison) B. Experimental group- Has the 1 independent variable (Test)

variables Variables- Conditions that can change Independent Variable- a variable that the scientist manipulates Dependent Variable- depends on the conditions set up in the experiment. Control Variables- variables kept constant

Gathering Data comes from an experiment & need to be repeated. Lesson 1.2 The Nature of Science Gathering Data If data match predictions, hypothesis is supported. If data do not match predictions, hypothesis is rejected. comes from an experiment & need to be repeated. Did You Know? Gulls are protected by the Migratory Bird Treaty Act, and government agencies like the U.S. Fish and Wildlife Service continually collect data on seagull populations and habitats. 8

Types of Data Qualitative- Description of data without numbers and uses ONLY words. Ex: the Grass grew taller. Quantitative- Description of data with numbers ex.: the grass grew 5 inches

Scientific Theory-Building Lesson 1.3 The Community of Science Scientific Theory-Building Hypothesis-testable explanation for a narrow set of phenomena Theory- broader explanation for a wider range of observations. Both: Testable multiple lines of evidence replicated to be accepted by the scientific community. 10

Peer Review A formal way for researchers to get comments and criticism from the scientific community Scientists will study something Write about their results Journal editor sends the article out for review Peer reviewers read the article and provide feedback to the editor Journal editor sends it back to the scientists for revision and resubmission, accepts article or rejects it for failing to meet standards.

Read the information below and then answer the questions. SpongeBob and Patrick love to go jellyfishing. They wondered if a new brand of jellyfish bait would help them catch more jellyfish. To test their idea, they bought a big container of bait for their next 3 trips to their top-secret fishing spot. SpongeBob fished without any bait, while Patrick used the new bait. Both of them kept track of how many jellyfish they caught in 30 minutes, which is shown in the chart. SpongeBob Patrick 25 24 18 28 26 19 Which person was the control? 2. What is the independent variable? 3. What is the dependent variable? 4. Based on the data, how would you rate the new bait?

Read the information below and then answer the questions. SpongeBob and Patrick love to go jellyfishing. They wondered if a new brand of jellyfish bait would help them catch more jellyfish. To test their idea, they bought a big container of bait for their next 3 trips to their top-secret fishing spot. SpongeBob fished without any bait, while Patrick used the new bait. Both of them kept track of how many jellyfish they caught in 30 minutes, which is shown in the chart. SpongeBob Patrick 25 24 18 28 26 19 Which person was the control? SpongeBob 2. What is the independent variable? Jellyfish Bait 3. What is the dependent variable? Number of jellyfish caught 4. Based on the data, how would you rate the new bait? The bait appears to have helped a small amount, but shouldn’t be rated as a great deal. Overall Patrick caught 2 more jellyfish than SpongeBob.

Read the information below and then answer the questions. SpongeBob loves to grow flowers for his pal Sandy, who loves big, colorful flowers. He found a new brand of seeds coated with a special “booster” fertilizer that said it would produce huge flowers. He planted 5 of the new seeds in one container and 5 of the old brand of seeds in another container. He placed both containers on a sunny windowsill and watered them every day. He measured the diameter of each flower, which is shown in the chart. Old Seeds 10 cm 12 cm 14 cm 6 cm 8 cm New Seeds 16 cm Which group was the control? 2. What is the independent variable? 3. What is the dependent variable? 4. What is the average diameter for each group? 5. Which seeds are the best for big flowers?

Read the information below and then answer the questions. SpongeBob loves to grow flowers for his pal Sandy, who loves big, colorful flowers. He found a new brand of seeds coated with a special “booster” fertilizer that said it would produce huge flowers. He planted 5 of the new seeds in one container and 5 of the old brand of seeds in another container. He placed both containers on a sunny windowsill and watered them every day. He measured the diameter of each flower, which is shown in the chart. Old Seeds 10 cm 12 cm 14 cm 6 cm 8 cm New Seeds 16 cm Which group was the control? The seeds without the booster fertilizer 2. What is the independent variable? Booster fertilizer on the new seeds 3. What is the dependent variable? Size or diameter of the flower 4. What is the average diameter for each group? Old = 10 cm, New = 12 cm 5. Which seeds are the best for big flowers? New seeds w/ the booster

Science Skills: Variables For the first 4 problems indicate the independent variable and dependent variable. Follow the directions for Problem 5 as given. Write your answers on a sheet of loose-leaf paper.

A variable is something that can vary or change A variable is something that can vary or change. What are the variables in this statement? This sample problem will give you the answer in the next slide. The time it takes to run a 10 km race depends on the amount of training the runner does. Click to check your answers

The time it takes to run a 10 km race depends on the amount of training the runner does. The independent variable is the amount of exercise. The dependent variable is the time it takes to run a 10 km race. It is not enough to say just “time” or “training” – you must describe the I.V. and tell how the D.V. is measured.

What are the variables in this statement? Problem 1: The temperature of water is measured at different depths in a lake Independent variable: Dependent variable: .

What are the variables in this statement? Problem 2: The more water a plant gets, the taller it will grow. Independent variable: Dependent variable:

What are the variables in this statement? Problem 3: The number of puppies in a litter is determined by the weight of the mother dog. Independent variable: Dependent variable:

What are the variables in this statement? Problem 4: The Texas A & M Extension Service has been counting the number of coyotes in Bexar County. Will the number of coyotes have any effect on the rabbit population? Independent variable: Dependent variable:

Problem 5: Lemon trees receiving the most water produce the largest lemons. a. Create a problem question. b. Identify the independent variable: c. Identify the dependent variable: d. List 2 possible constants: e. Explain what you might use for a control.