Intro. My website is what you should turn to if you lose something or forget what your HW is, OR.if you are absent!!!

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2 Intro All of my powerpoints, notes, and most handouts can be found on my website at - please use this website regularly as it is always updated! My website is what you should turn to if you lose something or forget what your HW is, OR.if you are absent!!!

3 Science Goals are to investigate and understand the natural world, to explain events in the natural world, and to use those explanations to make useful predictions

4 Biology Study of life Important b/c many of the advances in science and their social implications are related to biology How do you use it every day?

5 Science and Society Science must take societal issues into account. Biology plays a major role in the research, development, and production of food, medicine, and other consumer items.

6 Applications of Biology Human biology sleeping rhythms, basic needs of the body Global ecology oil spills, global warming Biotechnology-changes in DNA/proteins Environmental biology- nature Can you think of other applications?

7 Branches of Biology Anatomy Botany Cell biology Conservation biology Ecology Genetics Marine biology Pathology Zoology

8 Central Themes in Biology Cellular basis of life Information and heredity Matter and energy Growth, development, and reproduction Homeostasis Evolution Structure and function Unity and Diversity of Life Interdependence in nature Science as a way of Knowing

9 Biology and Current Events Human Genome Project Viruses Environment

10 Science is a METHOD Understanding the natural world using observations and experimentation. To be useful, results must be repeatable and verifiable by other scientists

11 Pseudoscience The word pseudo means fake, and the surest way to spot a fake is to know as much as possible about the real thing.science False science Pseudoscience cannot be investigated and explained in terms we can understand. The primary goal of science is to achieve a more unified understanding of the physical world/pseudosciences are more likely to be driven by ideological, cultural, or commercial goals Ex: astrology, UFO-ology, creationism

12 Scientific Method 1. Observe and state a problem 2. Form a testable hypothesis 3. Design and conduct an experiment 4. Collect Data 5. Draw a Conclusion

13 Observe and State a Problem Observation uses all of the senses. Different than an inference (an assumption based off of an observation). 2 types of observations: Quantitative and Qualitative Quantitative = observations that involve numbers (there are 24 students in class) Qualitative = observations that involve description (most students are wearing red)

14 Scientific Observations The green sea turtle laid 286 eggs, 250 hatched, and 120 hatchlings survived. The red eyed tree frog has pronounced nuptial pads on his hind legs. Scientists use all of their senses to make observations.

15 Hypothesis A solution to a problem Must be testable Predicts an outcome Often seen as an if then because statement Example: If I add Miracle Grow to a plant then it will grow taller because the plant will have more nutrients to utilize.

16 Scientific Theory Model that is supported by data from many testable hypotheses and for which little, if any, opposing data have been found. Ex: theory of evolution Make predictions from a theory (ex: there should be Observable differences and similarities between modern organisms and fossils found in rocks).

17 Theory of Evolution There is variation in all populations of organisms. The env. interacts with the population in a way that individuals better adapted to the env. will produce more offspring than those who are less fit. Overtime this natural selection produces organisms well suited to their env.

18 How Charles Darwin used methods of science Darwin made observations during his travels. He developed a hypothesis of how species change over time. He examined his data to see whether or not they supported the hypothesis After more study he concluded that evolution occurs and published his results.

19 Experiment Is a procedure to test the hypothesis A variable is any factor that can change in an experiment A good/valid experiment changes only ONE variable at a time so you know which variable is responsible for your results. An experimenter changes ONE factor and then observes and records what happens

20 A Controlled Experiment Has 2 groups: The control group and the experimental group Both groups are set up exactly the same except you change ONE factor (or variable) in the experimental group. Control give you something to compare the experimental group to.

21 Variables Dependent Variable: The variable that is observed and changes because of the manipulated (independent) variable in an experiment (also called responding variable) Independent Variable: the variable that is changed by the scientist(also called manipulating variable)

22 Miracle Grow experiment Adding the Miracle Grow independent variable Growth rate of plants dependent variable Plant with Miracle Grow: experimental group Plant without Miracle Grow: control group

23 Repeat, Repeat, Repeat The best experiments make several trials with the independent variable

24 Data The results of your experiment may have two types of data Quantitative Qualitative Data should always be organized Organize data as charts, tables, or graphs

25 Graphs Can make patterns and trends in data easier to recognize and understand. Rules of Graphing: Label each axis and include units Independent variable goes on X axis Dependent variable goes on Y axis Each interval should be equal Include a DESCRIPTIVE title

26 Axes? Independent variable? Dependent variable?

27 Identify a data point

28 What are the increasing and decreasing trends? Draw a conclusion

29 Conclusion After you analyze your data, you can come up with your conclusion The conclusion will support or reject your hypothesis Then you should retest your experiment!

30 Summary of the SM 1) State Observations about a problem you ve identified 2) Form a Hypothesis about the problem (if then ) 3) Design an Experiment to test the hypothesis 4) Collect Data 5) Form a Conclusion 6) Retest

31 Modeling Can you explain what is happening in this diagram?

32 What is happening in this diagram?

33 Metric System Developed by the French in the late 1700 s. Based on powers of ten, so it is very easy to use. Used by almost every country in the world, with the notable exception of the USA. Especially used by scientists. Abbreviated SI, which is French for Systeme International.

34 le Metric Prefixes Regardless of the unit, the entire metric system uses the same prefixes. Common prefixes are: kilo = 1000 centi = 1/100 th milli = 1/1000 th 1 meter = 100 centimeters= 1000 millimeters

35 le Length Length is the distance between two points. The SI base unit for length is the meter. We use rulers or meter sticks to find the length of objects.

36 Mass Mass is the amount of matter that makes up an object. A golf ball and a ping pong ball are the same size, but the golf ball has a lot more matter in it. So the golf ball will have more mass. The SI unit for mass is the gram. A paper clip has a mass of about one gram. The mass of an object will not change unless we add or subtract matter from it. le

37 le Measuring Mass We will use a electronic balance to measure mass. Gravity pulls equally on both sides of a balance scale, so you will get the same mass no matter what planet you are on.

38 le Weight Weight is a measure of the force of gravity on an object. Your weight can change depending on the force of gravity. The gravity will change depending on the planet you are on.

39 le Volume Volume is the amount of space contained in an object. We can find the volume of box shapes by the formula Volume = length x width x height In this case the units would be cubic centimeters (cm 3 ). So a box 2 cm x 3 cm x 5cm would have a volume of 30 cm 3 V = L x W x H

40 le Base Unit for Volume The base unit for volume is the Liter. We measure volume with a graduated cylinder.

41 Graduated Cylinders copyright cmassengale Liquids form curved, upper surfaces when poured into graduated cylinders To correctly read the volume, read the bottom of the curve called the meniscus

42 le Water Displacement to find volume We can use water displacement to find the volume of objects that are not boxed shaped. We can put water in a graduated cylinder. If a rock causes the level to rise from 7 to 9 ml, the the rock must have a volume of 2-mL.

43 Metric Conversions

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45 F to C Deduct 32, then multiply by 5, then divide by 9 C to F Multiply by 9, then divide by 5, then add 32 C F Description Water boils Hot Bath Body temperature Beach weather Room temperature Cool Day 0 32 Freezing point of water Very Cold Day Extremely Cold Day (and the same number!) Celsius to Fahrenheit: Fahrenheit to Celsius: C = F ( F - 32) / 1.8 = C

46 Graphing Visual representations of numerical data. Help to see patterns and trends A way to organize data Line Graphs change over time Bar Graphs - compare different things in a related category

47 Line Graphs X axis the Independent variable Y axis the Dependent variable

48 Bar Graphs Same thing X axis Independent variable Y axis Dependent variable

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50 The Compound Light Microscope

51 Calculating Total Magnification Total magnification = ocular lens x objective lens

52 Microscopic measurement High power field diameter low-power field diameter (um) x low power magnification = high power magnification

53 Orientation through the microscope

54 8 Characteristics of ALL Living Things: 1. Living things Reproduce 2. Living things Grow and Develop 3. Living things are made of Cells 4. Living things are based on a Genetic Code 5. Living things maintain homeostasis 6. Living things need Food to produce Energy 7. Living things Respond to their environment 8. Living things Evolve because of Adaptations

55 Levels of Organization

56 Intro to Statistics A data set includes: Mode- # that appears most often Mean average sensitive to extremes Median- # that appears in the middle of an ordered finite list insensitive to extremes When data is distributed normally all three can be helpful

57 Standard Deviation Measures how spread out the data is from the mean Lower standard deviation the data is closer to the mean The more likely the independent variable is causing the changes in the dependent variable

58 The Grid method to figure out SD X X (X-X) (X-X) 2 = /n-1 /n-1 = SD

59 What do these symbols mean? X X (X-X) (X-X) 2 X = sample X = mean Take average of samples (add up samples and divide by 5) 130/5 = 26 Sample mean = = = = = 2 Square each value from last box to get rid of negatives

60 Then what? = sum of squares = 18 n= sample size /n-1 = 18/4 = is variance /n-1 = take square root of variance 4.5 = 2.12 = SD

61 Why n-1 In the sample standard deviation formula dividing by n-1 provides a better estimate of unbiased results When 1 is subtracted in the denominator of the equation then the number is smaller and the standard deviation is larger- so it is a more conservative estimation and compensates for error better.

62 To Calculate Standard Deviation Grid Method Calculate the mean (average) Take the difference of the mean from each of the values Square the differences Sum the squared differences Divide by the sample size minus 1 Take the square root Let s Practice data set is (1,2,3,4,5) Did we get about 1.58? * Remember that standard deviation is the square root of the variance!

63 Quick Video Standard Deviation