Exploring and Classifying Life

1. Exploring and Classifying Life Chapter 1

2. What is Science? Section 1

3. What is Science? • Science is an organized way of studying things and finding answers to questions • Series of steps to solve problems  scientific method • BrainPop • Safety Rap

4. M&M Lab

5. You will be organizing and counting M&M candies to find out which color M&M is the most plentiful in each bag.

6. Question • Which color of M&M is most plentiful?

7. Hypothesis • If I count each color of M&M in a bag then _________ will be the most plentiful because _______________________________________________________.

8. Procedure • Do NOT eat anything in lab. • Open a bag of M&Ms. • Count the numbers of each color. • Record in chart.

9. Data

10. Graph Number of M&M v. Colors of M&M in a bar graph • Label the x-axis as Colors of M&Ms  horizontal axis • Label the y-axis as Numbers of M&Ms vertical axis • Make your graph as large as possible & colorful • Glue or staple onto your lab paper

11. Conclusion • What did your hypothesis say? • Was your hypothesis correct? wrong? • Include your observations and data • Give explanations. • Why would this information be important or useful?

12. Next Step???? • Talk with your lab partners and come up with 2 questions about M&Ms that could be answered by doing a lab activity

13. Vocabulary • Hypothesis  an educated guess or possible outcome to a problem • Procedure  set of directions or steps to follow • Data  Info gathered during an investigation • Graph  picture of your data

14. Conclusion  An answer to your question; was your hypothesis correct? • Variable  things that are changed in an experiment • Control  Things that are NOT changed in an experiment

15. Theory or Law? • Scientific Law – a RULE that describes a pattern in nature • Does not try to explain why • Scientific Theory - Attempt to explain a pattern observed repeatedly in the natural world • Can Δ w/ new data

16. Safety • Follow all safety rules during an experiment • Must make an 80% on lab safety quiz

17. Section Check 1 Question 1 This diagram shows a way to use scientific methods to solve a problem. According to the diagram, if a hypothesis is not supported by data then you should _______.

18. Section Check 1 • change the data so that • they do support the • hypothesis • B. find a different problem to • solve • C. propose a scientific theory • D. revise the hypothesis and • perform new experiments

19. Section Check 1 Answer The correct answer is D. Scientific methods are an organized way to solve a problem in science. This series of procedures involves forming a hypothesis that can be tested.

20. Section Check 1 Question 2 What is the definition of a control in a scientific experiment? Answer A control is the standard to which the outcome of a test will be compared. Controls help you determine how to interpret your data.

21. Section Check 1 Question 3 A statement about how things work in nature that seems to be true all the time is a _______. A. conclusion B. hypothesis C. law D. variable

22. Section Check 1 Answer The correct answer is C. Although laws can be modified as more information becomes known, they are less likely to change than theories.

23. Living Things Section 2

24. What are living things like? • Any living thing  organism • All organisms share similar traits

26. 1. Living things are organized • Cell  smallest unit of an organism that can carry on all the functions of life • Orderly structure • Contains hereditary material

27. 2. Living things respond • Stimulus  anything that causes a Δ • Response  reaction to a stimulus Homeostasis Stimulus Response Your body temperature rises because of exercise

28. 3. Living things use Energy • All energy ultimately comes from the Sun Some organisms make their own food from the Sun’s energy Some organisms eat plants for energy Heterotrophs Autotrophs

29. 4. Living things grow, develop, and die • Development  Δ that take place during the life of an organism • Lifespan  length of time an organism is expected to live

30. 5. Living things reproduce • Must replace individuals that die

31. List the characteristics of living things discussed in this video clipStar the ones that are different than what we have discussed.

32. What do Living things need? • Place to live • Raw materials • Water • Oxygen • Food • Different requirements for different organisms

33. Homework • Find 2 pictures of living things and 2 pictures of non-living things. • Either out of a magazine, real photos or you can even draw them, glue or tape them into your notebook. • Under each, list the characteristics the thing does or does not have that makes it alive or non-living. • Bring them to class and be prepared to share with the class whether they are living things or non-living things and why.

34. Section Check 2 Question 1 What is the smallest unit in a cat that carries on the functions of life? Answer The cell is the smallest unit. All organisms are composed of cells. Cells take in materials from their surroundings and use them in complex ways.

35. Section Check 2 Question 2 Pulling your hand back when you accidentally touch a hot pan on the stove is an example of what characteristic of living things? A. growth and development B. organization C. reproduction D. response to stimuli

36. Section Check 2 Answer The correct answer is D. The hot pan is an example of a stimulus. Living things can respond to both external and internal stimuli.

37. Section Check 2 Question 3 Give an example of two raw materials that you need to survive. Answer Some possible answers include: water, food, and oxygen. Some bacteria and plants can make food from raw materials in their surroundings.

38. Where does life come from? Section 3

39. Two ideas • Living things come from non-living things • Living things come only from other living things

40. Timeline Foldable • Information on page 20 in textbook • Glue last page of foldable into NB

41. 1668 • Francesco Redi • Decaying meat in jars & covered some • Maggots appeared only on uncovered meat • Conclusion: maggots hatched from fly eggs & not from the meat

42. 1745 • John Needham • Heated broth in flasks • Became cloudy w/ microorganisms • Conclusion: they developed spontaneously from the broth • (WRONG!)

43. 1768 • Spallanzani • Heated broth in sealed flasks • Only opened ones became cloudy

44. 1859 • Louis Pasteur • Boiled broth in open S-necked flasks • Only became cloudy when tilted & exposed to dust in the S-neck • Conclusion: no such thing as spontaneous generation

45. 1924 • Oparin Hypothesis • Earth’s early atmosphere contained no oxygen, but did have ammonia, hydrogen, methane, & water vapor • Chemical reactions triggered by • E from Sun • Lightning • Earth’s heat • New molecules washed into Earth’s oceans  primordial soup

46. 1953 • Miller and Urey • Sent electric currents through gasses • Cooled & condensed into liquid that contained amino acids (found in present-day cells)

47. Section Check 3 Question 1 This diagram shows an experiment Louis Pasteur conducted with boiled broth and S-necked flasks. Why did microbes only grow in the bottom flask?

48. Section Check 3 Answer Microbes from the air settled out at the bottom of the S-neck and only entered the broth when it was tilted so that the broth touched this area. This experiment by Pasteur helped disprove the theory of spontaneous generation.

49. Section Check 3 Question 2 Which one of the following examples supports the theory of biogenesis? A. kittens are produced from cats B. milk is produced by cows C. rain is produced by rain clouds D. stimuli produce responses

50. Section Check 3 Answer The correct answer is A. The theory of biogenesis states that living things come only from other living things.