Biology: The Study of Life

1. Biology: The Study of Life

2. I. Science means ‘to know’ (in Latin) A. Science is: • A body of knowledge • A process to learn about the world B. Biology is: • Study of Life • Biologists study the diversity of Life

3. I. Characteristics of Living Things: 1. Living things are made up of cells 2. Living things reproduce (not essential for survival but essential for continuation of species (a group of organisms that can interbreed and produce fertile offspring in nature) 3. Living things change: growth and development 4. Living things adjust to their surroundings (stimulus/response interactions) 5. Maintain homeostasis (balance internal condition) 6. Living things adapt and evolve 7. All Living things must Obtain and use energy 8. Have DNA Living Organisms – possess all of the characteristics of life

4. So, What Is The difference:

5. Homeo…. What??? • Homeostasis: Process by which organisms maintain constant and stable internal conditions. ie: In order to survive, there are several conditions that your body must remain stable. Like body temperature, salt and sugar levels, etc. Your body works like the furnace in your home.

6. The Scientific Method: a method of investigation involving observation and theory to test scientific hypotheses • Hypothesis: An educated guess based upon an observation. • Prediction: A prediction is a statement or claim that a particular event will occur in the future. Usually written as an If /Then statement. • Observation: Using your senses to gather data. • Inference: The process of making decisions about what the data means.

7. Types of Observations:

8. Observation Vs.Inference Activity • Mrs. Wade will be absent for the rest of the term. She won the lottery and thus decided to take a cruise around the world with her friends, Mrs. Walton and Mrs. Fernandez. She has left each team a box containing 3 personal items. She would like you to make 2 observations and two inferences about each item (you have 5 minutes for this activity). • Non-related example: You observed that the ground was wet. Therefore, you infer that it had just rained.

9. Applying The Scientific Method make observations / state problem form hypothesis design controlled experiment collect data analyze results may not support hypothesis may support hypothesis draw conclusion / publish form a new hypothesis

10. B. Parts of a Controlled Experiment 1. Types of Variables • Independent variable (aka Manipulated variable): • a factor that is manipulated to see what the result will be • Dependent variable (aka Responding variable): • a factor that responds to the changes in the independent variable

11. Dependent Vs. Independent Variables

12. In other words…

13. Parts of a Controlled Experiment Control Group: the group for which the testing conditions are not applied (AKA the Placebo). Experimental groups: • the groups where all conditions are held constant EXCEPT the one being tested Controlled variables: Variables that the experimenters keep the same throughout the experiment.

14. An Example Experiment Mrs. Fernandez’s son, Dominick, would like to know what will happen to his gummy bears if he places them in water. So, he obtains three (3) gummy bears (all are of the same brand). He places one in 20 mls of water for 3hrs, the other for 12 hrs, and the last for 24 hrs. He uses a 25ml graduated cylinder each bear. 3 mL 6 mL 0 mL

15. Your Turn…. • What is the independent variable in Dominick’s experiment? In what axis do graph it? • What is the dependent variable in the experiment? In what axis do you graph it? • What are the controlled variables in the experiment?

16. C. Drawing a Conclusion The conclusion should always have two main parts. • Confirm or reject the hypothesis • Was the hypothesis correct? • Overall statement of what was learned • What happened and why did it happen? • What’s the main idea?

17. D. Publishing Results • When a hypothesis has been tested and supported many times, a theory is formulated and published. • A theory is the best explanation science has to offer about a problem.

18. III. Other things to keep in mind: A. Always use metric system! • Distance: meters • Volume: liters • Temperature: oC • Mass: grams How big are these four ticks?

19. 1 2 3 MetersLitersGrams How do you use the “ladder” method? 1st – Determine your starting point. 2nd – Count the “jumps” to your ending point. 3rd – Move the decimal the same number of jumps in the same direction. Starting Point Ending Point __. __. __. 2 3 1 Ladder Method KILO1000Units HECTO100Units DEKA10Units DECI0.1Unit CENTI0.01Unit MILLI0.001Unit 4 km = _________ m How many jumps does it take? 4. = 4000 m

20. Kinds of DATA 1. Quantitative: produces numerical data that can be comparatively analyzed in graphs and tables a. Tables: Title Table, Columns & Rows have titles b. Graphs: -3 main types: line Graphs (measures change/ time), bar (used for comparing), & circle (shows %) 2. Qualitative: Descriptive data; written descriptions of observations

21. Gummy Bear Lab Read lab directions in lab hand-out and on board • Conduct the lab. • Clean up (everything must be spotless when lab is completed). • Graph and answer questions • Turn in assignment.

22. Let's Review

23. 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 Several days pass Manipulated Variables: gauze covering that keeps flies away from meat 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. Redi’s Experiment onSpontaneous Generation

24. Identifying Variables • Two groups of students were tested to compare their speed working math problems. Each student was given the same problems. One group used calculators and the other group computed without calculators. • What is the independent/manipulated variable? • What is the dependent/responding variable? • What is the controlled variable?

25. Identifying Variables • A study was done with an electromagnet system made from a battery and wire wrapped around a nail. Different sizes of nails were used and the number of paper clips that the electromagnet could pick up was measured. • What is the manipulated variable? • What is the responding variable? • What are the controlled variables?

26. Identifying Variables • A study was attempted to find if the length of the string in a string telephone affected its sound clarity. • What is the independent variable? • What is the dependent variable? • What are the controlled variables?

27. Your Turn.. Do the next three examples on your own and see how well you understand the concept.

28. Identifying Variables • An experiment was performed to determine how the amount of coffee grounds could affect the taste of coffee. The same kind of coffee, the same percolator, the same amount and type of water, the same perking time, and the same electrical source were used. • What is the manipulated variable? • What is the responding variable? • What are the controlled variables?

29. Identifying Variables • Students of different ages were given the same puzzle to assemble. The puzzle assembly time was measured. • What is the independent/manipulated variable? • What is the dependent/responding variable? • What is the controlled variable?

30. Identifying Variables • A study was done to find if different tire treads affect the braking distance of a car. • What is the independent variable? • What is the dependent variable? • What is the controlled variable?

31. But That’s NOT All! A law is a statement of fact that describe, in an action or set of actions. It is generally accepted to be true and universal, and can sometimes be proven mathematically. For example, the law of gravity or Newton’s laws of motion. What is a scientific LAW? But then what is a THEORY? A THEORY is an explanation of a set of related observations or events based upon proven hypotheses and verified multiple times by detached groups of researchers. One scientist cannot create a theory; he can only create a hypothesis. For example, the theory of relativity or evolution.

32. But That’s NOT All ALL! • How is THEORY used in everyday speech that is scientifically incorrect? • Bryant might say that he has a theory that Mrs. Wade will yell at the class today… • What would be a more ACCURATE word to use? • If he had made the same statement but had replaced theory with hypothesis, THEN he would be scientifically correct!

33. Oh no… Here come the metric problems! Practice, practice, practice until your good becomes your better and your better becomes your best!

34. A. 1 meter or 105 centimeters B. 4 kilometers or 4400 meters C. 12 centimeters or 102 millimeters D. 1200 millimeters or 1 meter km Metric Units m cm mm The basic unit of length in the metric system in the meter and is represented by a lowercase m. Standard: The distance traveled by light in absolute vacuum in 1⁄299,792,458 of a second. Metric Units 1 Kilometer (km) = 1000 meters 1 Meter = 100 Centimeters (cm) 1 Meter = 1000 Millimeters (mm) Click the image to watch a short video about the meter. Which is larger?

35. 1 centimeter = 10 millimeters What is the length of the line in centimeters? _______cm What is the length of the line in millimeters? _______mm What is the length of the line to the nearest centimeter? ________cm HINT: Round to the nearest centimeter – no decimals. Measuring Length How many millimeters are in 1 centimeter? Ruler: http://www.k12math.com/math-concepts/measurement/ruler-cm.jpg

36. Kilogram Prototype A. 1 kilogram or 1500 grams B. 1200 milligrams or 1 gram C. 12 milligrams or 12 kilograms D. 4 kilograms or 4500 grams kg Metric Units cg mg g Mass refers to the amount of matter in an object. The base unit of mass in the metric system in the kilogram and is represented by kg. Standard: 1 kilogram is equal to the mass of the International Prototype Kilogram (IPK), a platinum-iridium cylinder kept by the BIPM at Sèvres, France. Metric Units 1 Kilogram (km) = 1000 Grams (g) 1 Gram (g) = 1000 Milligrams (mg) Click the image to watch a short video about mass. Which is larger? Kilogram Prototype Image - http://en.wikipedia.org/wiki/Kilogram

37. Measuring Mass We will be using electronic balances to find the mass of various objects in this course. A weigh boat, paper towel of some container with be placed on the balance first and you will tare it, zero it out. The the objects are placed in the container and on the scale. The digital read-out has two decimal places, which is the mass of the object in grams. Top Image: http://www.southwestscales.com/Ohaus_Triple_Beam_750-SO.jpgBottom Image: http://www.regentsprep.org/Regents/biology/units/laboratory/graphics/triplebeambalance.jpg

38. Measuring Mass – Electronic Balance a- make sure the balance reads 0.00 g b-place weigh boat or container you will use to hold the material that is to be massed on balance and press ON button just long enough for the read-out to once again show 0.00 g (tare weigh boat) c. remove the weigh boat and put the material in it d. carefully place full weigh boat on balance and read to 2 decimal places e- remove items, clean up, & zero out balance

39. kL Metric Units cL mL L Volume is the amount of space an object takes up. The base unit of volume in the metric system in the liter and is represented by L or l. Standard: 1 liter is equal to one cubic decimeter Metric Units 1 liter (L) = 1000 milliliters (mL) 1 milliliter (mL) = 1 cm3 (or cc) = 1 gram* Which is larger? Click the image to watch a short video about volume. A. 1 liter or 1500 milliliters B. 200 milliliters or 1.2 liters C. 12 cm3 or 1.2 milliliters* * When referring to waterLiter Image: http://www.dmturner.org/Teacher/Pictures/liter.gif

40. What causes the meniscus? A concave meniscus occurs when the molecules of the liquid attract those of the container. The glass attracts the water on the sides. Measuring Volume We will be using graduated cylinders to find the volume of liquids and other objects. Read the measurement based on the bottom of the meniscus or curve. When using a real cylinder, make sure you are eye-level with the level of the water. What is the volume of water in the cylinder? _____mL Top Image: http://www.tea.state.tx.us/student.assessment/resources/online/2006/grade8/science/images/20graphicaa.gifBottom Image: http://morrisonlabs.com/meniscus.htm

41. Measuring Liquid Volume What is the volume of water in each cylinder? Images created at http://www.standards.dfes.gov.uk/primaryframework/downloads/SWF/measuring_cylinder.swf A B C Pay attention to the scales for each cylinder.

42. 9 cm 8 cm 10 cm We can measure the volume of irregular object using water displacement. Amount of H2O with object = ______About of H2O without object = ______Difference = Volume = ______ http://resources.edb.gov.hk/~s1sci/R_S1Science/sp/en/syllabus/unit14/new/testingmain1.htm Measuring Solid Volume We can measure the volume of regular object using the formula length x width x height. _____ X _____ X _____ = _____

43. 1 2 3 MetersLitersGrams How do you use the “ladder” method? 1st – Determine your starting point. 2nd – Count the “jumps” to your ending point. 3rd – Move the decimal the same number of jumps in the same direction. Starting Point Ending Point __. __. __. 2 3 1 Remember the Ladder Method KILO1000Units HECTO100Units DEKA10Units DECI0.1Unit CENTI0.01Unit MILLI0.001Unit 4 km = _________ m How many jumps does it take? 4. = 4000 m

44. Lets Practice Metric Conversions!!! Write the correct abbreviation for each metric unit. 1) Kilogram _____ 4) Milliliter _____ 7) Kilometer _____ 2) Meter _____ 5) Millimeter _____ 8) Centimeter _____ 3) Gram _____ 6) Liter _____ 9) Milligram _____ Try these conversions, using the ladder method. 10) 2000 mg = _______ g 15) 5 L = _______ mL 20) 16 cm = _______ mm 11) 104 km = _______ m 16) 198 g = _______ kg 21) 2500 m = _______ km 12) 480 cm = _____ m 17) 75 mL = _____ L 22) 65 g = _____ mg 13) 5.6 kg = _____ g 18) 50 cm = _____ m 23) 6.3 cm = _____ mm 14) 8 mm = _____ cm 19) 5.6 m = _____ cm 24) 120 mg = _____ g

45. Conversion Challenge 1. kg 2. m 3. g 4. ml 5. mm 6. L 7. km 8. cm 9. mg 10. 2 g 11. 104000 m 12. 4.8 m 13. 5600 g 14. .8 cm 15. 5000 ml 16. 0.198 kg 17. 0.075 l 18. 0.5 m 19. 560 cm 20. 160 mm 21. 2.5 km 22. 65000 mg 23. 63 mm 24. 0.12 g 25. < 26. > 27. = 28. = 29. < 30. >

46. Differentiate between Compound Light Microscopes and Electron Microscopes light electrons eyepieceobjective much greater magnification 2000

47. Label the parts of the microscope: a- eyepiece b- stage c- diaphragm d- coarse adjustment e- fine adjustment f- arm g- objective h- base a d e f g b c h

48. Microscopes • What is a light/compound microscope? • http://www.southwestschools.org/juniorschool/jsfaculty/Microscopes/compoundscope.html

49. Microscopes Allows scientists to view a universe too small to be seen with a light microscope. They don’t use light waves; they use electrons (negatively charged electrical particles) to magnify objects up to two million times. What is an electron microscope? What is the difference between TEM (transmission electron microscope) and a SEM (scanning electron microscope)? -> click on cool linkhttp://school.discoveryeducation.com/lessonplans/interact/vemwindow.html TEMs allows beams of electrons to go through the specimen while SEMs beams of electrons bounce off of the specimen and result in a 3D image. All images are black and white…why?