1. Science of Biology Notes

2. First of all, what is science?
Draw a vertical line on your paper, and label the two sides as “science” and “not science”
Brainstorm a few examples of specific academic disciplines on each side
(besides the normal broad high school classes like English, Math, Science, Social Studies)
Take a minute

3. What is Science? (1-1)
The root ­sci- means “to know”. Science is one way of investigating the world in which we live. Science strives to:
explore and understand the natural world,
explain events in the natural world, and
use those explanations to make useful predictions.
Are some things unpredictable?

4. Things that are not science include things like…
Art
Religion
Literature
Opinion

5. Is science better than these things?
No! it is simply another way of exploring the world in which we live
Science can only concern itself with testable things and\or observable things

6. Is scientific knowledge a set truth?
In our scientific explanations, we explain how things work using the knowledge we have to explain natural phenomena
When our knowledge base changes, our explanation may change

7. What is Science? (1-1)
Scientists use observations (process of gathering information by using your five senses) to gather data.
They also use known data to make inferences (a logical interpretation of the data based on past experiences).
Practice…

8. Determine in the picture if it is an observation (O) or an inference (I)
_____ There are 2 doors.
_____ The people are fighting because someone ate their cookies.
_____ One door is closed.
_____ They are hitting each other hard.
_____ Glass is broken. I O I O

9. What do scientists do? BASIC SKILLS:
1. Observing- Noting the properties of objects and situations using the five senses
2. Classifying- Relating objects and events according to their properties or attributes (Involves classifying places, objects, ideas, or events into categories based on their similarities.)
3. Space/Time Relations- Visualizing and manipulating objects and events, dealing with shapes, time, distance, and speed

10. What do scientists do? BASIC SKILLS:
4. Using numbers- Using quantitative relationships, e.g. scientific notation, error, significant numbers, precision, ratios, and proportions
5. Measuring- Expressing the amount of an object or substance in quantitative terms, such as meters, liters, grams, newtons, etc.
6. Inferring- Giving an explanation for a particular object or event
7. Predicting- Forecasting a future occurrence based on past observations or the extension of data

11. What do scientists do? INTEGRATED SKILLS
8. Defining Operationally- Developing statements that present a concrete description of an object or event by telling one what to do or observe.
9. Formulating models- Constructing images, objects, or mathematical formulas to explain ideas
10.Controlling variables- Manipulating and controlling properties that relate to simulations or events for the purpose of determining causation in experimental research design

12. What do scientists do? INTEGRATED SKILLS
11. Interpreting Data- Arriving at explanations, inferences, or hypotheses from data that have been graphed or placed in a table (this frequently involves concepts such as mean, mode, median, range, frequency, distribution, chi-square test, t test)
12.Hypothesizing- Stating a tentative generalization of observations or inferences that may be used to explain a relatively larger number of events but that is subject to immediate or eventual testing by one or more experiments in experimental research design
13.Experimenting- Testing a hypothesis through the manipulation and control of independent variables and noting the effects on a dependent variable; interpreting and presenting results in the form of a report that others can follow to replicate the experiment using experimental research design

13. How Scientists Work
“The” Scientific Method Scientists solve problems, but the method may vary based on the problem The three types of investigations:
Experimental Research Design
Correlation
Descriptive Investigation

14. Steps to Experimental Scientific Investigation (The Scientific Method):
1. Observe – make an observation of the world around you. There are two kinds of observations:
Qualitative observation – descriptive observation
Ex: The plant is green.
Quantitative observation – a numerical observation.
Ex: The flask contains ml. There are 4 pennies.
Which kind of observation? Let’s practice!

15. Determine if the statement is qualitative (A) or quantitative (B).
_____ The sky is blue.
_____ There are 4 clouds.
_____ There are 3 hills.
_____ The first hill is small.
_____ The clouds are small.
_____ There are a total of 38 birds. B B A A B

16. Franceso Redi
400 years ago, people believed that living things appear spontaneously from non-living matter (spontaneous Generation). Francesco Redi however wanted to disprove this idea. He considered it likely that flies laid eggs too small for people to see.

17. 2. Ask a question – based on your observation, ask a question to investigate.
Ex. Redi asked the question “How do new living things, or organisms, come into being?”
3. Research - Look in books, journals and the internet to make additional observations and research about the questions you made from your observation.

18. 4. Formulate a hypothesis: - Propose a scientific explanation to the question being observed and researched. The statement must be testable. (“Which is best?” does not lend itself to being tested). At the end of the investigation, you will either accept or reject your hypothesis.
Ex. If meat is left uncovered, then flies will leave eggs on the meat, creating maggots.

19. 5. Perform a controlled experiment - Develop and use the experimental design to test your hypothesis. Whenever possible, the hypothesis should be tested by an experiment in which only one variable is changed at a time. All other variables should be kept unchanged, or controlled.
Testing fertilizers on plant growth? Keep all other factors constant!

20. Ex. Redi created a controlled experiment in which only 1 variable was deliberately changed each time. Redi was able to determine that when the gauze was not present, flies could reach the meat and maggots would appear. When gauze was present, flies could not reach the meat and no maggots would appear.

21. Variables: Factor being tested
Controlled- Variables that are kept constant
Independent- Variable being manipulated (in a graph found on the x-axis or the horizontal axis)
Dependent- Variable that responds (in a graph found on the y-axis or the vertical axis)
Control Group – the group where the independent variable is NOT applied. Meaning, nothing is changed. Used for comparison.

22. A way to remember variables
Dependent
Responding
Y - axis
Manipulated
Independent
X - axis

23. Independent variable? ____________ Dependent Variable? _____________
Controlled Variables? _____________
Control Group? ________________
Cover on the jar
Maggots
Type of meat, size of jar
No cover on the jar

24. Repeat your experiment!
The more times you do it, the more accurate your data and results will be!!

25. 6. Observe again - Collect data (measurements) and perform analysis on the data using graphs and charts

26. 7. Draw conclusions - State whether or not the evidence supports the hypothesis based on your data and analysis.
Please notice that we do not prove hypotheses! Proof exists when the chance for error is 0. There is always some chance for error (no matter how small it is) and this existence of chance error means we cannot prove anything in true, honest, science.

27. 8. Report back to the community – Experiments’ results can be used by other to help them with their own experiments. This is what keeps science progressing.

28. What is the difference between a hypothesis, a theory, and a law?
A hypothesis is a possible explanation for a set of observations. It has not yet been thoroughly tested.

29. What is the difference between a hypothesis, a theory, and a law?
A theory is a well tested explanation that unifies a broad range of observations.
A theory explains observations simply and clearly, and predictions can be made from them.
It is widely accepted by the scientific community.
Theory of Plate Tectonics

30. What is the difference between a hypothesis, a theory, and a law?
A law is a summary of observed natural events: they are less comprehensive than theories and normally are associated with a mathematical expression. It is also widely accepted by the scientific community.
Law of Universal Gravitation

31. Studying Life What is Biology?
Etymology: “bio” means life, “-ology” means the study of-
Characteristics of Living Things: all living things have all eight things in common:

32. 1) They are made up of units called cells.
Studying Life
1) They are made up of units called cells.

33. 2) Reproduction (sexually or asexually)

34. 3) Has a universal genetic code (DNA or RNA)

35. 4) Grows and develops

36. 5) Responds to the environment

37. 6) Obtains and uses materials and energy

38. 7) homeostasis- maintains a stable internal environment

39. 8) Evolution- Groups change over time

40. Branches of Biology –
Biology is studied at many levels of organization from simple to complex:
1) Molecules – groups of atoms
Atoms 
Molecules 

41. 2) Cell – smallest functional unit of life

42. 3) Groups of cells – tissues, organs, and organ systems

43. 4) Organism – individual living system

44. 5) Population – group of organisms of one type that live in the same area

45. 6) Community – populations that live together in a defined area

46. 7) Ecosystem – community and its nonliving surroundings

47. 8) Biosphere – the part of Earth that contains all ecosystems

48. Tools and Procedures (1-4)
Biologists use metric measurement (the SI system) to gather and interpret data.
SI is the universal measurement system.

49. Tools and Procedures (1-4)

50. Conversions
The metric system is universal measurement system based on the number 10. The meter is the distance value, the gram is the mass value, and the liter is the volume value.

51. Conversions
If you want to change a larger unit into a smaller unit, move the decimal point to the right.
If you want to change a smaller unit to a larger unit move the decimal point to the left.
Example problems:
Convert 100 g to kg g =
kL = ________________ L
.1 kg
7.4

52. Scientific Notation to make large or small numbers easier to read
Numbers that are very small (many numbers after the decimal) have negative exponents
Numbers that are very large (many numbers before the decimal) have positive exponents

53. Scientific Notation
The goal is to have a single non-zero number to the left of the decimal (1-9) and the exponent at the end tells you how many decimal places over in which direction you would move to get to the original number.
Scientific Notation is really only useful if it will make the number shorter. If the number does not have several zeros in front or behind of the number taking up space, scientific notation will only make the number longer. Keep this in mind when converting.

54. Scientific Notation Example:
kg is easier to read as 1.0 x kg
cm is easier to read as x 109 cm
Practice problems:
g = _____________________
cm = _______________________
14698 g = _____________________________
x 1012
x 10-4
14698

55. Graphing- how a scientists shows patterns in data collected.
There are several kinds of graphs; not all of them are useful for data communication. Which type of graph is appropriate for which situations?

56. Line Graph
Line graph - compares two things in which items on one axis affect the items on the other axis. If you are comparing anything to time, it is usually a line graph.
(Ex. Amount of CO2 in the atmosphere over the last 6 decades)

57. Line Graph

58. Bar graph - compares two or more values. (Ex
Bar graph - compares two or more values. (Ex. Number of students with red hair in each class)

59. Bar Graph

60. Pie Chart- effective in showing proportions or percentages of a whole thing. (Ex. Comparing the percentage vote that each candidate received in the election)

61. Pie Chart

62. Graphing
Always draw lines with a ruler, use pencil, and use map pencils when necessary. Make sure your graph contains all components:
Title – tell what you are comparing or displaying (be descriptive).
X-axis – label and give scale.
Y-axis – label and give scale.
Key – give meanings of the symbols and colors used on the graph.
Data points – clearly marked, and label them if you do not have grid lines.

63. Microscopes
Biologists use microscopes to see living things that are too small for the unaided eye. The two basic categories of microscopes are:

64. 1) Light microscope – produces magnified images by focusing visible light rays. This microscope can be used to magnify up to 1000 times

65. 2) Electron microscope – produce magnified images by focusing beams of electrons. This kind is used to magnify tens and hundreds of thousands of times for extremely small object like a virus.
The hair on the leg of a fly (magnified by a factor of 1000)
Salt crystals on the antennas of an insect (magnified by a factor of 5000)

66. Other techniques and tools
Cell cultures - in order to study cells under a controlled condition, a biologist can take a single cell and place it in a Petri dish with nutrient solution to help the cell regenerate and fill the whole dish. This cell culture can be
used to isolate a single kind of cell, or study interactions between cells and chemicals.

67. Other techniques and tools
2. Cell fractionation - in order to study a single part of a cell, the cells can be lysed (burst open) and the broken cells can be added to a liquid and placed in a tube. This tube can be placed in a centrifuge which spins the tubes at high speeds which
causes cell parts to settle at different levels based on their density, the densest parts will land on the bottom.

68. Other techniques and tools
3. Autoclave - in order to sterilize tools and kill anything a scientist may have been growing to test, the must kill it with an autoclave. The large steel machine uses heat and pressure to raise the temperature
above normal boiling point of water to a temperature in which no bacteria, viruses, or spores can survive.