1. Chapter 1 The science of biology

2. 1-1 What is Science?
an organized way of using evidence to learn about the natural world.
also used to describe the body of knowledge built up over the years
Always changing (Pluto, 2006)

3. What are the goals of science?
investigate and understand the natural world.
Collect data/ observations
To explain events in the natural world
use those explanations to make useful predictions.

4. Thinking like a scientist…
Observation: the process of gathering information about events or processes in a careful, orderly way.

5. Thinking like a scientist…
Data: the information gathered from observations
Quantitative: involve numbers/measurements
Qualitative: descriptive/ not easily measured
Find patterns/trends

6. Thinking like a scientist…
Inference: a logical interpretation based on prior knowledge or experience (data)
Footprints/fossils
Scientists may use inferences at first but MUST backup with facts

7. Explaining and Interpreting Evidence
Hypothesis: proposed scientific explanation for a set of observations
May be accepted or rejected
Must be able to be tested…
Using controlled experiments and collecting new data
…and re-tested
Validity
Reliability

8. Collaboration Scientists and researchers often work in teams
Critical analysis/sharing of ideas
Review process helps to ensure valid results

9. Science is always changing
A continuous process involving:
Asking questions
Observing
Making inferences
Testing hypotheses
A good scientist is a skeptic of both new and old ideas
Men vs. women

10. Scientific Thinking
Scientists are trained to use a scientific methods as a guide to make intelligent decisions
However…

11. Other factors involved in decision making
Society/community
Economic considerations
Laws
Morals/ethics
Stem cell research?
Abortion?

12. 5 questions a biologist might ask about:

13. 1-2 How Scientists Work Ask questions and test them! Scientific Method
State the problem
Collect information
Form a hypothesis
Design and conduct an experiment
Record observations and data
Check results/retest
Draw your conclusions
Communicate your results

14. Designing a Controlled Experiment
Variables must be controlled
Dependent/responding variable
Independent/ manipulated variable
Controlled variables
Record results/analyze findings
Draw a conclusion

15. Spontaneous Generation as an Example
What if we wanted to test it?
Francesco Redi’s hypothesis (p.9)

16. Repeating Investigations
Anton van Leeuwenhoek- “animalcules”
John Needham challenges Redi
“SG just needs the right conditions”
Lazzaro Spallanzani adds his two cents
Boils gravy longer- seals flask
Some argued SG needed air (a “life force”)
Pasteur settles it with his curved flask

17. The Scientific Method:
State the problem
Collect information
Form a hypothesis
Design and conduct an experiment
Record observations and data
Check results/retest
Draw your conclusions
Communicate your results

18. When Experiments Are Not Possible…
Oscar Pistorius Olympic Debate
Field studies
Ethical concerns
If they are careful, scientists are still able to discover reliable patterns to make inferences about

19. So what if your hypothesis is accepted?
Scientific Theory: a well tested explanation that unifies a broad range of observations
a currently acceptable idea- universally accepted to be true
NOT a fact
Scientific Law = fact (ex: gravity)

20. 1-3 Studying Life bio = “life” logy = “the study of”
How do we know what is “living” and what is “nonliving”?

21. 8 Characteristics of Living Things
1. All living things are made up of cells
Unicellular
Multicellular

22. 2. All living things reproduce
Sexual
Asexual

23. 3. All living things are based on a universal genetic code
DNA determined the traits you receive from your parents

24. 4. All living things grow and develop
Increase in size
Cell division for specific “parts”

25. 5. All living things obtain and use materials and energy
To grow and develop
To simply stay alive
Metabolism: the breakdown of materials an organism uses to carry out its life processes

26. 6. All living things respond to their environment
Stimulus
External
Internal

27. 7. All living things maintain a stable environment
Homeostasis- internal feedback mechanism
Shivering and sweating

28. 8. All living things, viewed as a group, change over time.
evolution

29. Studying Biology
Different branches: anatomy, botany, microbiology, taxonomy, cytology, etc.
Levels of Organization
Molecular
Cellular
Groups of cells
Organisms
Populations
Communities
Ecosystems
Biosphere

30. 1-4 Tools and Procedures
The Metric System- a common decimal system of units based on multiples of 10
KHDUDCM: “King Henry Doesn’t Usually Drink Chocolate Milk”
Common Metric Units
Length: meter
Mass: gram
Volume: liter
Temperature: Celcius

31. Analyzing Data
Today, computers do the bulk of biological data analysis
Tables and Graphs

32. Microscopes Light microscope Electron microscope
Up to 1000x magnification
Compound light microscopes
Two lenses- light passes through an organism
Dyes and stains
Electron microscope
Can view very small organisms
Must be used in a vacuum
TEM (thru) and SEM (over surface)

36. Laboratory Techniques
Cell cultures
Single cell placed in a nutrient dish- grows into a “culture” of cells
Cell fractionation
Separates the different cell parts for individual study
Uses a blender and centrifuge

37. Vocabulary Review
1. This is the study of the natural world. It can also mean the body of knowledge we’ve built up based on these studies.
A. biology
B. anatomy
C. science
D. observation

38. 2. This occurs when living things come from nonliving things.
A. metabolism
B. homeostasis
C. hypothesis
D. spontaneous generation

39. 3. This is the process of gathering information about events/processes in a careful, orderly way.
A. data
B. inference
C. hypothesis
D. observation

40. 4. This is a logical interpretation based on prior knowledge and experiences.
A. inference
B. hypothesis
C. theory
D. qualitative data

41. 5. This is a well-tested explanation that unifies a broad range of observations.
A. theory
B. hypothesis
C. stimulus
D. inference

42. 6. This is a proposed scientific explanation for a set of observations.
A. inference
B. theory
C. hypothesis
D. a guess

43. 7. This type of reproduction requires only one parent.
A. asexual
B. sexual
C. unisexual
D. mating

44. 8. A collection of living matter enclosed by a barrier that separates it from it’s environment. It is the smallest unit of life.
A. atom
B. cell
C. molecule
D. organism

45. 9. A controlled experiment occurs when you change only this in your set-up.
A. responding variable
B. manipulated variable
C. dependent variable
D. control variable

46. 10. A signal to which an organism responds
A. homeostasis
B. stimulus
C. metabolism
D. trigger

47. 11. This is the branch of science that studies the living world.
A. science
B. anatomy
C. botany
D. biology

48. 12.This process requires an internal feedback mechanism in order to maintain internal balance in an organism.
A. metabolism
B. stimulus
C. homeostasis
D. thermostat

49. 13.This is a lab technique where cells are broken down into their individual parts.
A. cell fractionation
B. cell colonies
C. cell cultures
D. electron microscopy

50. 14. The two types of microscopes are:
A. compound and light
B. light and proton
C. compound and electron
D. light and electron

51. 15. The combination of chemical reactions through which an organism builds up and breaks down material as it carries out it’s life processes.
A. homeostasis
B. stimulus
C. metabolism
D. evolution

52. ANSWERS:
1. C
9. B
2. D
10. B
3. D
11. D
4. A
12. C
5. A
13. A
6. C
14. D
7. A
15. C
8. B