What Is Science???

1. What Is Science??? An organized way to observe and collect data to learn about the natural world The study of something in a manner that can be tested

3. Why is Science important? • It gives us a means to study nature. • It allows us to explain events in nature • It allows us to make predictions about the natural world. • Example: what will the long term affects of global warming be? • Another example: How would losing one species in a food web affect the other species in that food web.

4. Welcome to sc. method • http://www.youtube.com/watch?feature=player_embedded&v=KZaCy5Z87FA

5. The Scientific Method • Identify the Problem • Collect Background Info. • Form a Hypothesis • Perform experiments • Collect Data • Analyze Data • Form a Conclusion • Re-test Hypothesis

6. Observation Types • Qualitative: involve characteristics or traits that cannot be easily counted or measured • For example, The dog’s fur is black • Quantitative: involves characteristics that can be easily counted or measured • For example, The dog has two eyes.

7. What is Data? • The information gathered through observations and/or experimentation. • Sometimes referred to as evidence.

8. Defining an Inference • An inference is a logical interpretation based on prior knowledge and experience. • An example would be if you see an eagle with a white head, you might infer that it is a bald eagle. • Based on the way people dress we make inferences all the time. I. e. if a person wears nice clothes they have lots of money, or if they pierce their nose they like punk rock.

9. Hypothesis • A hypothesis is an explanation for a set of observations or an answer to a scientific question. • ALL HYPOTHESES HAVE TO BE ABLE TO BE TESTED OTHERWISE IT IS USELESS TO SCIENCE!!!!!

10. 3 Ways Hypotheses arise • Prior Knowledge • Logical inferences • Imaginative guesses

11. What is a Theory??? • It is a well tested hypothesis that has not been refuted by scientific observation or experimentation. • I. e. The Theory of Evolution, Geologic Time, or Plate Tectonics. These are all well established Scientific Theories.

12. Spontaneous generation • Aristotle originated idea 2300 years ago • This idea was not scientifically tested until 1668. • Redi proposed a new hypothesis for how life originates • Maggots from flies hypothesis.

13. Controlled Experiments • An experiment in which there is only one manipulated or independent variable. • All other variables need to be controlled • A manipulated Variable is a variable that is being changed • A controlled variable is a variable that is kept constant throughout the experiment • A responding variable is a variable that changes in response to the manipulated variable

14. Redi’s Experiment • Controlled experiment • Tested whether flies have anything to do with the emergence of maggots. • What is the manipulated variable? Why? • What are the controlled variables? Why? • What is the responding variable? Why?

15. Figure 1-8 Redi’s Experiment on Spontaneous Generation Section 1-2 OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat. HYPOTHESIS: Flies produce maggots. PROCEDURE Uncovered jars Covered jars Controlled Variables: jars, type of meat, location, temperature, time Manipulated Variables: gauze covering that keeps flies away from meat Several days pass Responding Variable: whether maggots appear Maggots appear No maggots appear CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous generation of maggots did not occur. Go to Section:

16. Figure 1-10 Spallanzani’s Experiment Section 1-2 Gravy is boiled. Flask is open. Gravy is teeming with microorganisms. Flask is sealed. Gravy is free of microorganisms. Gravy is boiled. Go to Section:

17. Figure 1-11 Pasteur’s Experiment Section 1-2 Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Go to Section:

18. Figure 1-11 Pasteur’s Experiment Section 1-2 Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Go to Section:

19. Figure 1-11 Pasteur’s Experiment Section 1-2 Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Go to Section:

20. Figure 1-11 Pasteur’s Experiment Section 1-2 Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Go to Section:

21. Pasteur Continued… • Why was Pasteur’s experiment so important? • It allowed air into the flask ended the last debate over spontaneous generation.

22. Field Observation Studies • Controlled experiments can not always be used • Instead scientists sometimes use Field Observation studies. • F. O. S. are when scientists observe nature and collect data without interfering in anyway. • I. e. a scientist studying Gorillas in the wild.

25. Section 1-3 Living Characteristics

26. Biology • The science that seeks to understand the living world. • Types of biologists includes: • Zoologists • Botanists • Marine biologists • And more specific types

27. Characteristics of Living Things • Made of cells • Have to reproduce • Based on genetic code (contain DNA) • Grow and develop • Use materials and energy • Respond to their environment • Maintain homeostasis • Change over time as a group (evolve)

28. Characteristics of Living Things Section 1-3 Characteristic Examples Living things are made up of units called cells. Many microorganisms consist of only a single cell. Animals and trees are multicellular. Living things reproduce. Maple trees reproduce sexually. A hydra can reproduce asexually by budding. Living things are based on a universal genetic code. Flies produce flies. Dogs produce dogs. Seeds from maple trees produce maple trees. Living things grow and develop. Flies begin life as eggs, then become maggots, and then become adult flies. Living things obtain and use materials and energy. Plants obtain their energy from sunlight. Animals obtain their energy from the food they eat. Leaves and stems of plants grow toward light. Living things respond to their environment. Despite changes in the temperature of the environment, a robin maintains a constant body temperature. Living things maintain a stable internal environment. Taken as a group, living things change over time. Plants that live in the desert survive because they have become adapted to the conditions of the desert. Go to Section:

29. Cells • Are the smallest units of an organism • Unicellular- means to only have one cell • Examples are bacteria and paramecium • Multicellular- means to have many cells • Examples include dogs, cats, and humans OH MY!

30. Reproduction • Production of viable offspring • Sexual reproduction- two cells unite to form the first cell of a new organism (egg and sperm) • Asexual reproduction- the new organism is identical to the parent cell it came from. • I. e. mitosis, binary fission

31. Grow and develop • All living things grow and develop • This often occurs in stages, such as our own embryonic stages or like the metamorphic stages of a butterfly

32. DNA- (deoxyribonucleic acid) • All living things have DNA in every cell that gives instructions to the cell.

33. Metabolism • Chemical reactions through which organisms builds up or breaks down materials. • Determines amount of energy used/needed

34. Homeostasis • This is how organisms keep their internal conditions relatively stable. • This homeostasis is constantly being threatened by the environment. • Think about the movie Biodome.

35. Evolve • Organisms change over time as a group • Remember the bacteria! • Over time organisms with useful characteristics survive to reproduce while non useful characteristics do not. This causes the individuals w/ non useful characteristics to decrease and the individuals w/ useful char. to increase in number. • Snake’s hind legs is a good example.

36. 8 Levels of Organization • Biosphere • Ecosystem • Community • Population • Organism • Groups of cells • Cells • molecules

37. Section 1-3 Figure 1-21 Levels of Organization The part of Earth that contains all ecosystems Biosphere Biosphere Ecosystem Community and its nonliving surroundings Hawk, snake, bison, prairie dog, grass, stream, rocks, air Populations that live together in a defined area Community Hawk, snake, bison, prairie dog, grass Group of organisms of one type that live in the same area Population Bison herd Go to Section:

38. Figure 1-21 Levels of Organization continued Section 1-3 Organism Individual living thing Bison Tissues, organs, and organ systems Groups of Cells Nervous system Brain Nervous tissue Smallest functional unit of life Cells Nerve cell Groups of atoms; smallest unit of most chemical compounds Molecules DNA Water Go to Section: