Presentation is loading. Please wait.

Presentation is loading. Please wait.

Chapter 1 The science of biology

Similar presentations

Presentation on theme: "Chapter 1 The science of biology"— Presentation transcript:

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.

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

Download ppt "Chapter 1 The science of biology"

Similar presentations

Ads by Google