Biology Chapter 1

1. Unit 1: The Nature
of Life
Chapter 1: The
Science of Biology
Ms. Petrucci
Biology

2. Chapter 1: The Science of
Biology
• Vocabulary
• 1-1
– Science
– Observation
– Data
– Inference
– Hypothesis
• 1-2
– Spontaneous generation
– Controlled experiment
– Manipulated (Independent) Variable
– Responding (Dependant) Variable
– Theory
• 1-3
– Biology
– Cell
– Sexual Reproduction
– Asexual Reproduction
– Stimuli
– Metabolism
• 1-4
– Metric system
– Microscopes
• Compound Light Microscopes
• Electron Microscopes
– SEM
– TEM
– Cell Culture
– Cell Fractionation

3. 1-1 What is Science?

4. Tell whether the following
statements are scientific:
• Why it rains:
– It rains because the clouds are crying.
– Enough water vapor must be available to a cloud
for precipitation to form.
• Where Babies come from:
– Fertilization can occur outside of an organism.
– Storks bring babies to the new parents.
• The sun:
– The sun is a really big bonfire.
– You can walk on the sun in the winter
because it is not as hot.

5. The Goal of Science
• The goal of science is to understand the natural
world. To achieve this goal, scientists make certain
assumptions. They assume that:
– Nature can be understood through systematic study.
– Scientific ideas are open to revision.
– Sound scientific ideas withstand the test of time.
– Science cannot provide answers to all questions.

6. The Goals of Science
1. Science deals only with the natural world
The supernatural is outside of the realm of
science

7. The Goals of Science
2. Collect and Organize Information

8. The Goals of Science
3. Propose explanations that can be tested

9. The Scientific Method
• There are basic methods of gaining knowledge that are common to all of science. At the
heart of science is the scientific investigation, which is done by following the scientific
method. A scientific investigation is a plan for asking questions and testing possible
answers. It generally follows the steps listed in the figure:

10. Science Begins with
OBSERVATIONS
• How good are your Observing Skills?

11. Think Like a Scientist…
• Make Observations
• Ask a Question
• Form a Possible Answer
(Hypothesis)
• Test the Idea and Collect
Data (from the observations)
• Make an Inference/Draw
Conclusions
• Communicate the Results
Quantitative vs Qualitative

12. Explaining and Interpreting
Evidence
• How Scientists develop a Hypothesis
– Use prior knowledge
– Make a logical inference
– Informed, creative imagination
• Accept or reject? (Support or Refute)
– Evaluating experimental results
– Gathering more data

13. Hypothesis or Not?
• Our universe is surrounded by another,
larger universe, with which we can have
absolutely no contact.
• Any two objects dropped from the same
height above the surface of the earth will
hit the ground at the same time, as long as
air resistance is not a factor.
• Occam’s Razor

14. Science as a Way of Knowing
• Science is an ongoing process
• Scientific understanding is ever-changing

15. Science and Human Values
• Journal Prompt
• Your journal entries should look like this:
8/25/2014
Make a list of things that you need to understand in order to
protect your life and the lives of others (include at least 5 different
things)
Start your list here
List each item on a new line
Make sure you have at least five items
Take 5 minutes to complete in
your journal:
Make a list of things that you
need to understand in order to
protect your life and the lives of
others (include at least 5
different things).
Make sure you include the date
and the prompt in your actual
journal (just like the picture)
and write legibly.

16. 1-2 How Scientists Work
• Systematically

17. Designing an Experiment
1. Make Observations/Ask a Question
2. Research/Form a Hypothesis
4. Record and Analyze Results
5. Draw a conclusion
– Communicate Results
– Repeat

18. Set up a Controlled Experiment
– Use only one variable
– Control (keep unchanged) all others
– Manipulated variable is changed
– Responding variable is observed
• Francesco Redi (1668)
• Needham (1748)
• Lazzaro Spallanzini (1765)
• Louis Pasteur (1800's)

19. Variables
• Dependent Variable
• Independent
Variable

20. Redi’s Experiment
• Spontaneous Generation

21. Needham’s Experiment
• Spontaneous generation can occur under
the right conditions. Was Redi wrong!?

22. • 1765
• Nonliving Gravy
does not produce
living things.
• New organisms
are produced only
by existing
organisms

23. • 1861
• Fixed the “no
air” claim of
Needham.
• Some flasks still
sterile today.

24. Disproved Spontaneous Generation!
Life can only come from other life.
Three Experiments

25. Practice the Scientific Method
• Think about how you
would test how the
amount of a certain
fertilizer determines if the
fertilizer would grow
taller plants.

26. Brainstorm
• Decide how you would go about
conducting an experiment or investigation
to study this.
• Identify the Dependant Variable and the
Independent Variable
• I will provide you results

27. Data
Does more fertilizer = better growth?
Analyze these results.

28. What if you Cannot
Experiment?
• When might an experiment not be
possible?
• How can we answer scientific questions
without experimentation?

30. What is a Theory??

31. 1-3 Studying Life
• What are the
Characteristics of living
things?
• How can live be studies
at different levels?
• Define Biology

32. To be classified as a living thing, an
object must have all eight of the
following characteristics:
• Living things:
– Are made up of units called cells
– Reproduce
– Are based on a universal genetic code
– Grow and develop
– Obtain and use materials for
energy
– Respond to their environment
– Maintain homeostasis
– Taken as a group, change over
time (evolution)

33. 1. Living things are made up of
units called cells
• Cell - smallest unit of life
– unicellular = single celled
– Multicellular = many celled

34. 2. Living Things Reproduce
• Sexual Reproduction
• Asexual Reproduction

35. 3. Living things are based on a
universal genetic code
http://www.pbs.org/wgbh/nova/genome/dna.html

36. 4. Living Things Grow and
Develop

37. Differentiation

38. 5. Living Things Obtain and
Use Materials and Energy

39. 6.Living Things Respond to
Their Environment

40. 7. Living Things Maintain a
Stable Internal Environment

41. 8. Living Things (Group)
Change Over Time

42. Big Ideas in Biology
• Science as a Way of Knowing
• Interdependence in Nature
• Matter & Energy
• Cellular Basis of Life
• Information and Heredity
• Unity & Diversity of Life
• Evolution
• Structure & Function
• Homeostasis
• Science, Technology & Society

43. Branches of Biology
• Zoology = animals
• Paleontology = ancient life
• Cytology = cells
• Botany = plants
• Entomology = insects
• Microbiology =
• Ecology =

44. Levels of Organization
• The living world can be organized into different levels. For
example, many individual organisms can be organized into
the following levels:
•Molecule
•Cell
•Tissue
•Organ
•Organ System
•Organism

45. More Organizational Levels
• There are also levels of organization
above the individual organism.
•Population
•Community
•Ecosystem
•Biome
•Biosphere

46. Diversity of Life
biodiversity

47. 1-4 Tools and Procedures
• What is the most
dangerous thing in
a Science Lab?

48. A Common Measurement
System
• Metric System – Base 10 System
– KHDDCM

49. How long are these snails?
How is Length measured? (what units?)
Snail 1
Snail 2
Snail 3

50. Volume
• How much space
something takes up
• Usually a measure of
liquids
• Use a
beaker or
graduated
cylinder.

51. Mass – not weight

52. Mass ≠ Weight

55. Temperature

57. How can a graph help biologist
analyze data?

58. Microscopes
Steroscope Compound
Microscope
Scanning Electron
Microscope

59. Stereoscope

60. Light Microscopes

61. Electron Microscope

62. Laboratory Techniques
• Cell Cultures – single cell grown on
nutrients will divide and form millions of
cells

63. • Cell Fractionation – technique in which
cells are broken into pieces and parts are
separated.
Laboratory Techniques

64. Working Safely in Biology
• Lab Safety Handout
• Lab One – Using a Compound Microscope
• Chapter Test Next Week!