Chapter 1

1. Chapter 1 Science in the 21st Century

2. What system do we use in science for making measurements? • Metric System Why do we use the Metric system and not the normal English system? • Base 10 is so much easier to use • 1000 meters in a kilometer • 1000 milligrams in a gram • Universal Metric system • Every country is using this system except US on a regular basis

3. Metric Measurement

4. Measurements in Science Unit Abbreviation Length Meters m Mass Gram g Volume Liter l Time Second s Temperature Celsius `C Density Mass/Volume g/l or g/cm3

5. To Measure the volume of a liquid: • Always use the smallest one that can fit the volume you need. • Use a 10 ml cylinder if you only need 5 ml • If you need 75 ml, use the 100 ml cylinder

6. Measuring with a Graduated Cylinder • Measure at the lowest curve of the meniscus • Use a dropper to help to level off the amount wanted

7. What is the volume?

8. Using the Displacement method to measure the volume of a solid object • Place 60 ml of water into a 100 ml GC. • Careful, slide the object into the GC. • Record the new volume of the water. • Lets say the new volume is 65 ml • Subtract the original volume of 60 from the new volume of 65 ml • 65 ml – 60 ml = 5 ml. The volume of the object is 5 ml

9. Displacement Method to determine volume

10. To measure distance or length • Use a metric ruler or meter stick • Each little line is 1 millimeter (mm) • The thickness of a paperclip’s side • 10 mm = 1 centimeter (cm) • The thickness of your pinky • 10 cm = 1 decimeter (dm) • The thickness of the palm of your hand • 10 dm = 1 meter (m) (From fingertips to shoulder) 1 mm 1 cm 1 dm

11. Converting in the Metric System • Kilo (k) = 1000 x a meter, liter or gram • Deci (d) = 1/10th of a meter • Centi (c) = 1/100th of a meter • Milli (m) = 1/1000th of a meter • Micro (u) = 1/1,000,000th of a meter or 1/1000th of a millimeter kilo deci milli Meter Liter Gram centi micro

12. Meter Liter Gram 1. Convert 150.53 centimeters to meters • Count how many spaces there are between the centimeters & meters and in which direction • …. 2 to the left • Now move the decimal place two places to the left • 150.53 • 1.5053 meters kilo deci milli centi micro

13. To MeasureTemperature: • Use a Thermometer. • We will only measure in degrees Celsius • Important temperatures: • Body temp ~ 37`C • Room temp ~ 21 `C • Water freezes at 0`C • Water boils at 100`C

15. What is Science? Science asks the same questions you did as a young child. What is that? Why does it do what it does? How does that happen? What happens if …? Science investigates and attempts to understand and explain events in nature.

16. How do you go about solving a problem?

17. How do we go about doing “Science”? The Scientific Method of course!! • An observation is made. • Which lead to a question • Do some research • Propose a hypothesis • Conduct a controlled experiment • Collect data and make observations • Analyze data • Make a conclusion

18. Spontaneous Generation Life arises from non-living matter or just suddenly appear. Abiogenesis Meat grows maggots Corn produces rats Bread breeds mold So what do you think of this theory?

19. How are new living organisms produced? • Question is stated Where do flies come from? • Now we need to form a hypothesis It’s a proposed answer to a question Must be specific and testable Francesco Redi (1668) Hypothesis: Flies lay small eggs on meat that become maggots

20. Redi’s Experiment • Set up a controlled experiment to test his hypothesis • Observations: No maggots appeared in the jar with the gauze on top.

21. Variables • Controlled variable/Constants: What is the same with both the control and experimental setup? Jar, meat, location, temperature, time, type of fly • Independent or Manipulative variable: The one factor or variable that is being tested Gauze covering the meat jars • Dependent (responding) variable: What might happen as a result of the change Whether maggots appear

22. Conclusion: Maggots are the result of flies laying tiny eggs on meat that develop into maggots Others experimented on Spontaneous Generation and all came to the same conclusion, that life only comes from other living things. This is called Biogenesis

23. Let’s Talk about Observations • Quantitative • Numbers (Quantity) • How many maggots, how big were they… • Qualitative • Use your senses (Please don’t taste them!) • What did they look like? • What did they smell like? • What color were they • How did they act when disturbed • Leave out Opinions and Assumptions • Do not say that the meat smelled bad. Explain the smell • Do not say that the meat must have been old. That’s an assumption

24. Activity • You and your partner have been given an unknown item. • You are to make and write down as many observations as possible of the item you have been given. • You are not allowed to change it in any way so please do not cut it, pierce it or damage it. When observing, we try to be as unobtrusive as possible. • You are allowed to use some of the metric equipment you have learned about.

25. Your Observations: Quantitative

27. The Scientific Method Cycle

28. Scientific Method 1. State the Problem 2. Form a Hypothesis • Set Up a Controlled Experiment With only 1 independent variable • Record Results (Data) Make Quantitative & Qualitative Observations Avoid assumptions or opinions Charts, tables, pictures, graphs 5. Analyze Data 6. Draw a Conclusion • Theory – is a time tested hypothesis Theory of Evolution of Big Bang theory

29. What is Biology? Biology is the study of living things and how they interact with each other and the environment.

30. What makes something a living thing? • In the space given in your notes, write down 4 characteristics of all living things. • Ask yourself: • What do all living things do? • What do all living things need? • What do all living things contain? • Share your list with a partner and then observe the 10 items in the back of the room. • Check off which ones possess your selected characteristics

31. What makes something a living thing? List the characteristic of living things. • ________________________________ • ________________________________ • ________________________________ • ________________________________ • ________________________________ • ________________________________

34. What makes something living? • Characteristics of Life • Made up of Cells • Have a level of Organization • Need a constant flow of Energy • Can respond to changes in the environment • Can Grow and Develop • Can Reproduce • Have a universal Genetic code

35. What makes something living? Characteristics of Life All living things… • …are made up of cells. Smallest living unit of all living things Unicellular or Multicellular.

36. 2…have a level of organization. Molecular and Cellular

37. Level of Organization SYSTEM ORGAN CELL TISSUE ORGANISM

38. 3…need a constant flow of Energy. Necessary for Metabolism - all the chemical processes taking place in the organism. Respiration, digestion, excretion, nerve impulse … Some make their own food like plants, from raw materials (Autotrophic), others need to process organic matter (Heterotrophic) to obtain energy.(like animals and fungus)

39. 4…are able to respond to their environment. Maintain an internal steady state – Homeostasis. Ex. Since the writing was difficult for you to see, you opened your eyes wider and also pupils dilated. Increased heart rate when stressed, Goosebumps and shivering. Pupil size to light and darkness

40. Process leads to Evolution (a change in a species over time)

41. 5…grow and develop. Your very first baby picture Process occurs by adding on more cells by cell division (making more cells of the same kind) and cell differentiation (cells becoming different to suit their various functions). Red blood cell White blood cell Nerve cells Easily flow in vessels Change shape to Like a wire to squeeze through conduct electrical intracellular spaces impulses

43. 6...reproduce. Adding on more cells or reproducing another organism Passing on of genetic information (DNA and genes) Not a necessary life process but needed for the continuation of the species. Sexual (involves the fusion of two cells) and Asexual (involves only 1 cell dividing) reproduction.

44. 7. …all living things are based on a universal genetic code • DNA • Contains your genetic information which will be passed on to the next generation

45. What makes something living? • Characteristics of Life • Made up of Cells • Have a level of Organization • Need a constant flow of Energy • Can respond to changes in the environment • Can Grow and Develop • Can Reproduce • Have a universal Genetic code

46. Review • Which characteristic of life is each of the following: • You were born • You started out as 1 cell and then 15-16 years later, you are you • You have cheek, nerve and skin cells that perform specialized functions • We eat and utilize our food • Our DNA is 99.9% the same and 98% to that of chimps • We sneeze when there is something irritating our nasal passages • Our bodies are made up of organs and organ systems • Responsible for the big difference between us and a flame

47. Vocabulary • We need to eat food to get energy • Plants are producers and make their own food • The rate at which all our chemical reactions take place • Amoeba has only 1 cell • Amoeba reproduce by copying its DNA and then splitting into two identical cells • Sperm and egg coming together • What contains the universal genetic code • Adding on more cells • Cells specializing to their function