Essential Question: How do biologists work safely?

1. Georgia Performance Standards:Use standard safety practices for all classroom laboratory and field investigations. Essential Question: How do biologists work safely?

2. Inro. Day 1 • Students will complete the info sheet • Explain Syllabus • Explain Lab Safety Contract • Show the location of emergency equipment.

3. Warm-up: • Read through safety scenarios. (posted on a transparency) • Students will discuss the correct and incorrect procedures

4. Safety Lab: • Students will complete the recognizing lab safety lab in groups and discuss answers with teacher via teacher-lead guided discussion

5. Georgia Performance Standards: • Evaluate how scientific knowledge is developed, how the process of science is used, and be able to analyze new material relative to past scientific knowledge and processes. • Essential Questions: • What is science? • What are common scientific methods? • What are laws, theories and hypotheses? • How are experiments conducted?

6. What is Science? An organized why of using evidence to learn about the natural world. What is the Goal of Science? To investigate and understand the natural world, to explain events in the natural world, and to use those explanations to make useful predictions. The Nature of Science:

7. Scientific Method: • How scientists workthe organized process scientists use to investigate the natural world • Start with a question, or problem • Observations are made to gather evidence (data) • Quantitative = numerical observations • Qualitative = descriptive observations

8. Interpret Evidence • Scientists make inferences, or logical guesses to explain observations • Explaining Evidence (Data) by Forming a Hypothesis • Hypotheses, or educated guesses are used to explain the evidence (data) • A hypothesis can be tested through a controlled experiment • A tested hypothesis has value in science because it helps scientists advance in scientific knowledge.

9. Set up a Controlled Experiment • Only one variable in changed at a time, and everything else is constant, or does not change. • Manipulated variable = changes on purpose (Independent variable) • Responding variable = changes in response to something (Dependent variable)

10. Drawing Conclusions • Use data from a controlled experiment to evaluate the hypothesis and draw a valid conclusion • Controlled experiments must be able to be repeated. • Scientists repeat results to be sure that the results match those already obtained.

11. Hypotheses (Educated guess) often cause scientists to develop new experiments that produce additional data Theory (well-tested explanation that unifies a broad range of observations) testing, revising and occasionally rejecting new and old theories never ends. no theory is considered absolute truth Hypothesis & Theories:

12. Recording and Analyzing Results Tables, charts, graphs Journals, lab notebooks Drawing Conclusions Use data from a controlled experiment to evaluate the hypothesis and draw a valid conclusion Results & Conclusions:

13. Flowchart Designing an Experiment Section 1-2 State the Problem Analyze Results Form a Hypothesis Draw a Conclusion Set Up a Controlled Experiment Publish Results Record Results Go to Section:

14. ACTVITY • Identifying experiment variables activity

15. Tools play a major role in science. A common system of measurement i replicate needed to replicate experiments. Collect data to analyze whether certain factors changed or remained the same. Biologists use a variety of techniques and tools to study cells. Safe procedures are used when carrying out investigations. Tools & Procedures

16. A Common System of Measurement • Most scientist use the metric system when collecting data and performing experiments. • A decimal system whose units are based on certain physical standards and are scaled on multiples of 10. • 1 meter (m) = 100 centimeters (cm) • 1 meter = 1000 millimeters (mm) • 1000 meters = 1 kilometers (km) • 1 liter (L) = 1000 milliliters (mL) • 1 liter (L) = 1000 cubic centimeters (cm3) • 1 kilogram (kg) = 1000 grams (g) • 1 gram = 1000 milligrams (mg) • 1000 kilograms = 1 metric ton (t) • 0°C = freezing point of water • 100°C = boiling point of water

17. Analyzing Biological Data • Scientists often record data in a table and then make a graph. • The graph of data can make a pattern of change much easier to recognize and understand. • Computers are also used to process data

18. Section 1-4 Making a Graph From A Data Table Water Released and Absorbed by Tree Absorbed by Roots (g/h) Released by Leaves (g/h) 20 Water released by leaves Time 15 8 AM 1 2 10 Relative Rates (g/h) 10 AM 5 1 12 12 PM 4 5 2 PM 6 17 Water released by leaves 4 PM 9 16 0 6 PM 14 10 8 AM 10 AM 12 PM 2 PM 4 PM 6 PM 8 PM 8 PM 10 3 Time When scientists collect data, they are often trying to find out whether certain factors changed or remained the same. Often, the simplest way to do that is to record the data in a table and then make a graph.

19. Experimental Design Activity • Temperature effects on algae growth

20. Microscopes are devices that produce magnified images of structures that are too small to see with the unaided eye. Light microscopes = produce magnified images by focusing visible light rays. Electron microscopes = produce magnified images by focusing beams of electrons Problems: magnification definition Microscopes

21. Light microscopes Study dead organisms Tiny organisms Live cells Electron microscopes Produce sharp images Only dead and preserved cells can be observed Microscopes

22. Cell Cultures to study, biologists sometimes place a single cell into a dish containing a nutrient solution. The cell is able to reproduce so that a group of cells, called a cell culture, develops from the single original cell. Cell cultures can be used to test cell responses under controlled conditions, to study interactions between cells, and to select specific cells for further study. cell fractionation to separate the different cell parts. Studying Cells

23. Homework • Complete the Graphing Skills Lab.

24. Ticket Out the Door • Why do scientists use a common system of measurement? • What is the difference in the way light microscopes and electron microscopes produce images? • Describe the technique and purpose of cell fractionation. • What types of objects can be studied with a light microscope? What types can be studied with an electron microscope? • It has been said that many great discoveries lie in wait for the tools needed to make them. What does this statement mean to you? If possible, include an example in your answer.