Biology 101 Chapter 1 PowerPoint

1. 1-1
Chapter 1
Biology:
The Science
of Life
Copyright © McGraw-Hill Education. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

2. 1-2
1.1 The Characteristics of Life
 In this section, the following objective will be covered:
 Explain the basic characteristics that are common to all
living things.

3. 1-3
Life is Organized
 Cell—smallest, most basic unit
of life
 Organisms may be
unicellular or multicellular.
 Cells are made up of
nonliving atoms and
molecules
 Tissues—made up of similar
cells
 Organ—made up of tissues
 Organ systems—organs working
together
 Organism—living thing made of
organ systems
 Population—group of the same
organism
 Community—all of the living
things in an area
 Ecosystem—the living and
nonliving things in an area
 Biosphere—the earth, where
all life exists

4. 1-4
The Levels of
Biological
Organization
 The levels of
organization from the
least to most complex
are atoms, molecules,
cells, tissues, organs,
organ systems,
organism, species,
population,
community,
ecosystem, biosphere.

5. 1-5
Life Requires Materials and Energy
 Life cannot be maintained without them.
 Food—building blocks and energy sources
Energy—capacity to do work
Metabolism—all chemical reactions occurring
in the cell
 Ultimate source of energy for nearly all life on
Earth is the sun
Photosynthesis transforms solar energy into
chemical energy of food

6. 1-6
Materials
Cycle and
Energy
Flows in an
Ecosystem

7. 1-7
Living
Things
Maintain
Homeostasis
Homeostasis—
maintenance of
internal conditions
within certain
boundaries
May be behavior—
moving to a warmer
area
May not require
conscious activity—
liver releases
stored sugar

8. 1-8
Living Organisms Respond
Living organisms respond to their
environment and to other organisms
Find energy and/or nutrients by interacting
with the environment
Ability to respond often results in movement
Responding to changes in the environment is
different from adapting/evolving

9. 1-9
Living Organisms Have Adaptations
That Lead to Evolution
 Adaptations: genetic traits that make
organisms suited to their way of life
 Some hawks catch fish, others are better at
catching rabbits.
Adaptations for flight and catching prey get
passed on to offspring over generations and
lead to a change in the species (evolution)
 Humans who live at extreme elevations
exhibit an adaptation that reduces the
amount of hemoglobin in the blood

10. 1-10
Living Organisms
Reproduce and Develop
 Every living thing can reproduce, or
make another organism like itself
 Bacteria and other single-celled
organisms simply split in two
 In multicellular organisms, the
reproductive process usually
begins with the union of egg and
sperm, producing an embryo
 Embryos grow according to genes
inherited from parents
 In all organisms, genes are made of
DNA
 DNA is the blueprint for living
things

11. 1-11
1.2 Evolution: The Core
Concept of Biology
 In this section, the following objective will be covered:
 Summarize the general characteristics of the domains and
major kingdoms of life.

12. 1-12
Evolution
 Evolution—process by which populations
accumulate adaptations over time to
become more suited to their
environments
 Explains the unity and diversity of life
 Evolutionary trees trace the ancestry of
life on Earth to a common ancestor

13. 1-13
An Evolutionary Tree

14. 1-14
Evolution by Natural Selection
Charles Darwin and Alfred
Russel Wallace both
independently came to the
conclusion that evolution
occurs by a process called
natural selection.
Charles Darwin wrote the
book, On the Origin of
Species, presenting
substantiating data.
Evolution is a core concept
of biology— explains so
many different types of
observations in every field
of biology.

15. 1-15
Environmental Change
Causes Evolution
Environments may change due to the influence of
living or nonliving factors
 Natural selection is a process that results in a
population adapted to the environment
 Some individuals of a population may possess
certain adaptations that make them better
suited to a new environment
 Individuals that are better suited to a new
environment tend to live longer and produce
more offspring
 The adaptations that result in higher
reproductive success increase in frequency
from one generation to the next, which is
evolution

16. 1-16
Hawaiian honeycreepers
All evolved from one
species of finch
Assortment of bill
types adapted to
different types of
food
Still share certain
characteristics from
common finch
ancestor—body
shape, nesting
behavior, etc.
Darwin said evolution is
descent with modification.

17. 1-17
Evolution of
Hawaiian
Honeycreepers

18. 1-18
Organizing the Diversity of Life
Taxonomy—discipline of naming and classifying
organisms according to certain rules
• Systematics—classifies organisms according to presumed
evolutionary relationship
• Categories of classification
• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species

19. 1-19
Life Is
Classified
into Three
Domains
The most inclusive and most general
classification is the Domain
 Domain Archaea
 Prokaryote—unicellular, lacks
membrane-bound nucleus
 May be representative of first
cells on Earth
 Domain Bacteria
 Prokaryote—unicellular, lacks
membrane-bound nucleus
 Found almost everywhere
 Domain Eukarya
 Eukaryote
 Unicellular or multicellular
 Membrane-bound nucleus
 Domain Eukarya is divided into
four kingdoms: Protista, Fungi,
Plantae, and Animalia

20. 1-20
Domain Archaea
Example
Magnified 8,330x
Capable of
living in extreme
environments.
Methanosarcina
mazei, a methane-
generating prokaryote.
(Archaea): © Eye of Science/Science Source

21. 1-21
Domain Bacteria
Example
Magnified 6,660x
Structurally simple but
metabolically diverse.
Escherichia coli, a
prokaryote found in our
intestinal tracts.
(Bacteria): © A. B. Dowsett/SPL/Science Source

22. 1-22
Domain Eukarya,
Kingdom Protista
Example
Magnified 250x
* Many systematics are suggesting that kingdom Protista be subdivided to
better reflect the evolutionary relationships of these organisms.
Diverse group of
eukaryotes, many
single-celled.
Euglena, an
organism with
both plant and
animal-like
characteristics.
(protists): © blickwinkel/Fox/Alamy

23. 1-23
Domain Eukarya,
Kingdom Plantae
Example
Multicellular
photosynthesizers.
The bristlecone pine,
Pinus longaeva, one of
the oldest organisms
on the planet.
(plants): © Brenda Tharp/Science Source

24. 1-24
Domain Eukarya,
Kingdom Fungi
Example
(fungi): © Corbis RF
Multicellular
decomposers.
Amanita-a
Mushroom.

25. 1-25
Domain Eukarya,
Kingdom Animalia
Example
Multicellular
organisms that
ingest food. Homo
sapiens-humans.
(animals): © Radius Images/Getty RF

26. 1-26
Each Organism Has a Unique
Binomial Name
First word is the genus
Second word is specific epithet (species)
Universally used by scientists to avoid
confusion of common names
The genus is capitalized and the species
lower case; typically written in italics
Example: Pisum sativum, the garden pea

27. 1-27
1.3 Science: A Way of Knowing
 In this section, the following objectives will be covered:
 Identify the steps of the scientific method.
 Describe the basic requirements for a controlled
experiment.

28. 1-28
Biology is a Science
Biology is the scientific study of life.
 Start with an observation
 Scientific method begins with
observations.
 May take advantage of
knowledge and experiences of
other scientists
 Develop a hypothesis
 Scientist uses inductive
reasoning—uses creative thinking
to combine isolated facts into a
cohesive whole.
 Hypothesis—possible explanation
for an event
 Consider only those that can
be tested.

29. 1-29
Flow Diagram for the
Scientific Method

30. 1-30
The Scientific Method
Make a prediction and perform experiments
• Experiments further observations and test a
hypothesis.
• Good experimental design, all conditions constant
except experimental variable
• Test group versus control group
• Data may suggest correlation.
• Does not necessarily mean causation
• Scientists are skeptics.
Develop a conclusion
• Is the hypothesis supported or not?
• Experiments and observations must be repeatable.

31. 1-31
Scientific
Theory
 The ultimate goal of
science is to understand
the natural world in
accepted explanations
for how the world works.
 Exp: cell theory and
gene theory
 Theory of evolution is
considered a unifying
concept in biology.
 Some biologists refer to
the principle or law of
evolution due to over
100 years of support by
so many observations
and experiments.

32. 1-32
An Example of a Controlled Study
Randomly divide participants into 3 groups:
Experimental group 1
receives Antibiotic A
Experimental group 2
receives Antibiotic B
Control group
receives a placebo
Hypothesis: Antibiotic B is better than
Antibiotic A in current use for the
treatment of ulcers.

33. 1-33
An Example of
a Controlled
Study: Results
Results determined
by endoscopy that
checks patients for
ulcers
 Double-blind
study—technician
doesn’t know
which group
patient is in

34. 1-34
An Example of a Controlled Study:
Conclusion and Next Steps
Conclusion—investigators conclude their
hypothesis is supported
Scientific studies
published in a
scientific journal
Undergoes a peer eview
process
General public usually
relies on secondary
sources, which may be
inaccurate
Be especially careful of
information on the
Internet

35. 1-35
1.4 Challenges Facing Science
 In this section, the following objective will be covered:
 Distinguish between science and technology.

36. 1-36
Technology
and Ethics
Technology—application
of scientific knowledge
for a practical purpose
Bioethics—branch of
ethics concerned with the
development and
consequences of
technology
Biodiversity is perhaps
the single most
significant bioethical
issue today.

37. 1-37
Human Influence on Ecosystems:
Biodiversity and Extinction
 Biodiversity—variation in life on Earth; refers to
numbers of different species
 Estimated 15 million species on Earth; around
two million classified
 Extinction—death of an entire species or
taxonomical group
 Estimated 400 species per day are lost due to
human activity
 Extinction affects biodiversity

38. 1-38
Human Influence on Ecosystems:
Emerging Diseases
Emerging diseases may result from
new and/or increased exposure to
animals or insect populations that
may act as vectors for disease
Change in human behavior and use
of technology has increased our
travel and exposure to infections

39. 1-39
Human Influence on Ecosystems:
Climate Change
Changes in the normal cycles of the Earth’s
climate that may be attributed to human
activity
Primarily due to imbalance in chemical
cycling of carbon due to burning of fossil
fuels and destruction of forests

40. 1-40
Chapter 1 Objective Summary
 You should now be able to:
 1.Explain the basic characteristics that are common to all
living things.
 2. Summarize the general characteristics of the domains and
major kingdoms of life.
 3. Identify the steps of the scientific method.
 4.Describe the basic requirements for a controlled
experiment.
 5.Distinguish between science and technology.