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© 2013 Pearson Education, Inc. Lectures by Edward J. Zalisko
PowerPoint® Lectures for Campbell Essential Biology, Fifth Edition, and
Campbell Essential Biology with Physiology,
Fourth Edition
– Eric J. Simon, Jean L. Dickey, and Jane B. Reece
Chapter 1 Introduction: Biology Today
2
• Biology is the scientific study of life.
– What is life?
• The study of biology encompasses
– a wide scale of size and
– a huge variety of life, both past and present.
THE SCOPE OF LIFE
The Properties of Life
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3 Properties of Life:
1) Order
2) Regulation
3) Growth and delopment
4) Energy Processing
5) Respons to the Environment
6) Reproduction
7) Evolution
2
4 Properties of Life:
1) Order
– All living things exhibit complex but ordered
organization
5 Properties of Life:
2) Regulation
– The environment outside an organism may change
drastically, but the organism can adjust its internal
environment,
6 Properties of Life:
3) Growth and development
– Information carried by DNA controls the pattern of
growth and development
3
7 Properties of Life:
4) Energy processing
– Organisms take in energy and use it to perform all
of life’s activities; they emit energy as heat
8 Properties of Life:
5) Response to the environment
– All organisms respond to environmental stimuli.
9 Properties of Life:
6) Response to the environment
– Organisms reproduce their own kind
4
10 Properties of Life:
7) Evolution
– Reproduction underlies the capacity of populations
to change (evolve) over time.
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
Emergent properties:
• At each level novel properties
emerge from the specific
arrangement and interactions of the
parts in an increasingly
sophisticated system.
• In simple terms the sum is greater
than the parts – Car analogy
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
7
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
20
• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
Nucleus
8
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• Biologists explore life at levels ranging from the
biosphere to the molecules that make up cells.
Life at Its Many Levels
1) Biosphere
2) Ecosystems
3) Communities
4) Populations
5) Organisms
6) Organ Systems and Organs
7) Tissues
8) Cells
9) Organelles
10) Molecules and Atoms
Atom
23 Ecosystems
• Each organism interacts continuously with its
environment.
– Organisms interact continuously with the living and
nonliving factors in the environment.
– All the living organisms in a specific area, along
with all of the nonliving factors with which they
interact, form an ecosystem.
© 2013 Pearson Education, Inc.
24 Ecosystems
• The dynamics of any ecosystem depend on two
main processes:
– recycling of chemical nutrients and
– flow of energy.
• Within ecosystems
– nutrients are recycled but
– energy flows through.
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25 Figure 1.3
ECOSYSTEM Inflow of light energy
Outflow of heat energy
Producers (plants and other photosynthetic organisms)
Chemical energy (food)
Cycling of
nutrients
Consumers (animals)
Decomposers (in soil)
26 Cells and Their DNA
• The cell is the level at which the properties of life
emerge.
• Cells are the lowest level of structure that can
perform all activities required for life.
• All organisms are composed of cells.
• Cells are the subunits that make up multicellular
organisms such as humans and trees.
© 2013 Pearson Education, Inc.
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• All cells share many characteristics.
– All cells are enclosed by a membrane that
regulates the passage of materials between the
cell and its surroundings.
– Every cell uses DNA as its genetic information.
Cells and Their DNA
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• We can distinguish two major types of cells:
1. The prokaryotic cell is
– simpler and usually smaller and
– characteristic of bacteria.
2. The eukaryotic cell is
– subdivided by internal membranes into different
functional compartments called organelles and
– found in plants and animals.
Cells and Their DNA
© 2013 Pearson Education, Inc.
29 Figure 1.4
Nucleoid
region Nucleus
Organelles
Prokaryotic cell (bacterium)
Smaller
Simpler structure
DNA concentrated in
nucleoid region, which is not enclosed by membrane
Lacks most organelles
• • •
•
• •
•
•
Larger
More complex
structure
Nucleus enclosed
by membrane
Contains many
types of organelles
Eukaryotic cell
Co
lori
zed
TE
M
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• All cells use DNA as the chemical material of
genes, the units of inheritance that transmit
information from parents to offspring.
• The chemical language of DNA
– is common to all organisms and
– consists of just four molecular building blocks with
names that are abbreviated as A, G, C, T.
Cells and Their DNA
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31 Figure 1.5
A DNA molecule
The four chemical building blocks of DNA
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• Genetic engineering has transformed the
pharmaceutical industry and extended millions of
lives.
Cells and Their DNA
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33 Figure 1.6
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• The entire “book” of genetic instructions that an
organism inherits is called its genome.
• The nucleus of each human cell packs a genome
that is about 3 billion chemical letters long.
Cells and Their DNA
© 2013 Pearson Education, Inc.
35 Life in Its Diverse Forms
• Diversity is a hallmark of life.
– The diversity of known life includes about 1.8
million species that biologists have identified and
named.
– Estimates of the total number of species range
from 10 million to over 100 million.
© 2013 Pearson Education, Inc.
36 Figure 1.7
13
37 Grouping Species: The Basic Concept
• Biodiversity can be beautiful but overwhelming.
• Categorizing life into groups helps us deal with this
complexity.
• Taxonomy is the branch of biology that names
and classifies species.
– It formalizes the hierarchical ordering of organisms
into broader and broader groups.
© 2013 Pearson Education, Inc.
38 The Three Domains of Life
• The three domains of life are
– Bacteria,
– Archaea, and
– Eukarya.
• Bacteria and Archaea have prokaryotic cells.
• Eukarya have eukaryotic cells.
© 2013 Pearson Education, Inc.
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• Eukarya include
– Kingdom Plantae,
– Kingdom Fungi,
– Kingdom Animalia, and
– Protists (multiple kingdoms).
• Most plants, fungi, and animals are multicellular.
• Protists are generally single-celled.
The Three Domains of Life
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• These three multicellular kingdoms are
distinguished by how they obtain food.
– Plants produce their own sugars and other foods
by photosynthesis.
– Fungi are mostly decomposers, digesting dead
organisms.
– Animals obtain food by ingesting (eating) and
digesting other organisms.
The Three Domains of Life
© 2013 Pearson Education, Inc.
41 Figure 1.8
Protists (multiple kingdoms)
Kingdom Animalia
Kingdom Fungi
Kingdom Plantae
DO
MA
IN E
UK
AR
YA
DO
MA
IN
AR
CH
AE
A
DO
MA
IN
BA
CT
ER
IA
42 Unity in the Diversity of Life
• Underlying the diversity of life is a striking unity,
especially at the lower levels of biological
organization.
– For example, all life uses the genetic language
of DNA.
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43
- Genome-wide variation from one human being to another can be up to
0.5% (99.5% similarity)
- Chimpanzees are 96% to 98% similar to humans, depending on how it is
calculated.
- Cats have 90% of homologous genes with humans, 82% with dogs, 80%
with cows, 79% with chimpanzees, 69% with rats and 67% with mice.
- Cows (Bos taurus) are 80% genetically similar to humans
- 75% of mouse genes have equivalents in humans, 90% of the mouse
genome could be lined up with a region on the human genome 99% of mouse
genes turn out to have analogues in humans
- The fruit fly (Drosophila) shares about 60% of its DNA with humans
- About 60% of chicken genes correspond to a similar human gene.
44 Unity in the Diversity of Life
• Underlying the diversity of life is a striking unity,
especially at the lower levels of biological
organization.
– For example, all life uses the genetic language
of DNA.
• Biological evolution accounts for this combination
of unity and diversity.
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45 EVOLUTION:
BIOLOGY’S UNIFYING THEME
• The history of life is a saga of a constantly
changing Earth billions of years old.
– Fossils document this history.
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46 Figure 1.9
47
• Life evolves.
– Each species is one twig of a branching tree of
life extending back in time through ancestral
species more and more remote.
– Species that are very similar, such as the brown
bear and polar bear, share a more recent
common ancestor.
EVOLUTION:
BIOLOGY’S UNIFYING THEME
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48 Figure 1.10
Millions of years ago
Giant panda
Common ancestor of
polar bear and brown bear
20 25 10 15 30 5
Common ancestor
of all modern bears
Ancestral
bear
Spectacled bear
Sloth bear
Sun bear
American black bear
Asiatic black bear
Polar bear
Brown bear
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49 The Darwinian View of Life
• The evolutionary view of life came into focus in
1859 when Charles Darwin published On the
Origin of Species by Means of Natural Selection.
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50 Figure 1.11a
51
• Darwin’s book developed two main points:
1. Species living today descended from a succession
of ancestral species in what Darwin called
“descent with modification,” capturing the duality
of life’s
– unity (descent) and
– diversity (modification).
2. Natural selection is the mechanism for descent
with modification.
The Darwinian View of Life
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52 Natural Selection
• Darwin was struck by the diversity of animals on
the Galápagos Islands.
• He thought that adaptation to the environment and
the origin of new species were closely related
processes.
– As populations separated by a geographic barrier
adapted to local environments, they became
separate species.
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53 Darwin’s Inescapable Conclusion
• Darwin synthesized the theory of natural selection
from two observations that were neither profound
nor original.
– Others had the pieces of the puzzle, but Darwin
could see how they fit together.
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• Observation 1: Overproduction and competition
• Observation 2: Individual variation
• Conclusion: Unequal reproductive success
– It is this unequal reproductive success that Darwin
called natural selection.
– The product of natural selection is adaptation.
• Natural selection is the mechanism of evolution.
Darwin’s Inescapable Conclusion
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55 Figure 1.12a
Elimination of individuals with certain traits
Population with varied inherited traits 1
2
56 Figure 1.12b
Increasing frequency of traits that enhance survival and reproductive success
Reproduction of survivors 3
4
57 Adaptation
• The beetles are said to have adapted to their
environment
• However, it is the beetle population that evolved
and adapted. Individuals do not evolve.
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58 Observing Artificial Selection
• Artificial selection vs natural selection
• Artificial selection is the selective breeding of
domesticated plants and animals by humans.
• In artificial selection, humans do the selecting
instead of the environment.
© 2013 Pearson Education, Inc.
59 Figure 1.13a
(a) Vegetables descended from wild mustard
Wild mustard
Cabbage from end buds
Cauliflower from flower clusters
Broccoli from flowers and stems
Kale from leaves
Kohlrabi from stems
Brussels sprouts from side buds
60 Figure 1.13b
(b) Domesticated dogs descended from wolves
Domesticated dogs Gray wolves
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61 Observing Natural Selection
• There are many examples of natural selection in
action.
– In Galápagos finches, beak size becomes better
suited to the size and shape of available seeds.
– Antibiotic-resistance in bacteria evolves in
response to the overuse of antibiotics.
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62
• Darwin’s publication of The Origin of Species
fueled an explosion in biological research.
– Evolution is one of biology’s best demonstrated,
most comprehensive, and longest-lasting theories.
– Evolution is the unifying theme of biology.
Observing Natural Selection
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63 THE PROCESS OF SCIENCE
• The word science is derived from a Latin verb
meaning “to know.”
– Science is a way of knowing, based on inquiry.
– Science developed from our curiosity about
ourselves and the world around us.
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64 THE PROCESS OF SCIENCE
• There are two main scientific approaches:
– Discovery science is mostly about describing nature.
– Hypothesis-driven science is mostly about
explaining nature.
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65 Discovery Science
• Science seeks natural causes for natural
phenomena.
– This limits the scope of science to the study of
structures and processes that we can observe and
measure directly or indirectly.
• The dependence on observations that people can
confirm demystifies nature and distinguishes
science from belief in the supernatural.
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• Verifiable observations and measurements are the
data of discovery science.
– In biology, discovery science enables us to
describe life at its many levels, from ecosystems
down to cells and molecules.
Discovery Science
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67 Figure 1.14a
68 Figure 1.14b
69 Discovery Science
• Discovery science
– can stimulate us to ask questions and seek explanations and
– uses a process of inquiry called the scientific method, consisting of a series of steps that provide a loose guideline for scientific investigations.
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70 Hypothesis-Driven Science
• Most modern scientific investigations can be described as hypothesis-driven science.
– A hypothesis is a tentative answer to a question—an explanation on trial.
– Although we don’t think of it in those terms, we use hypotheses in solving everyday problems, like figuring out why a TV remote fails.
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• Once a hypothesis is formed, an investigator can
use logic to test it.
– A hypothesis is tested by performing an
experiment to see whether results are as
predicted.
– This deductive reasoning takes the form of
“If…then” logic.
Hypothesis-Driven Science
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72 Hypothesis-Driven Science
Observation The remote doesn’t work.
Hypothesis The
batteries are dead.
Question What’s wrong?
Prediction With new
batteries, it will work.
• The mysterious case of the broken remote
25
73
Experiment supports
hypothesis; make more predictions
and test.
Observation The remote doesn’t work.
Hypothesis The
batteries are dead.
Question What’s wrong?
Experiment Replace
batteries.
Prediction With new
batteries, it will work.
Hypothesis-Driven Science
• The mysterious case of the broken remote
74 Hypothesis-Driven Science
Experiment does not support
hypothesis.
Experiment supports
hypothesis; make more predictions
and test.
Observation The remote doesn’t work.
Hypothesis The
batteries are dead.
Question What’s wrong?
Experiment Replace
batteries.
Prediction With new
batteries, it will work.
Revise.
The Process of Science:
Are Trans Fats Bad for You?
• One way to better understand how the process of
science can be applied to real-world problems is to
examine a case study, an in-depth examination of
an actual investigation.
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• Dietary fat comes in different forms.
• Trans fats are a non-natural form produced through
manufacturing processes called hydrogenation.
• Trans fats
– add texture,
– increase shelf life, and
– are inexpensive to prepare.
The Process of Science:
Are Trans Fats Bad for You?
© 2013 Pearson Education, Inc.
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• A study of 120,000 female nurses found that a diet
with high levels of trans fats nearly doubled the risk
of heart disease.
The Process of Science:
Are Trans Fats Bad for You?
© 2013 Pearson Education, Inc.
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• A hypothesis-driven study published in 2004
– started with the observation
– that human body fat retains traces of consumed
dietary fat,
– asked the question
– Would the adipose tissue of heart attack patients be
different from a similar group of healthy patients?
– formed the hypothesis
– healthy patients’ body fat would contain less trans fats
than the body fat in heart attack victims.
The Process of Science:
Are Trans Fats Bad for You?
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• Design experiment:
– The researchers set up an experiment to determine the
amounts of fat in the adipose tissue of 79 patients who
had experienced a heart attack.
• Collect data and analyze:
– They compared these patients to the data for 167
patients who had not experienced a heart attack.
• This is an example of a controlled experiment
– in which the control and experimental groups differ only
in one variable—the occurrence of a heart attack.
The Process of Science:
Are Trans Fats Bad for You?
© 2013 Pearson Education, Inc.
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• The results showed significantly higher levels of
trans fats in the bodies of the heart attack patients.
The Process of Science:
Are Trans Fats Bad for You?
© 2013 Pearson Education, Inc.
81 Figure 1.16
Heart attack patients
1.77
Control group
1.48
2.0
1.5
1.0
0.5
0
Tra
ns f
ats
in
ad
ipo
se t
issu
e
(g t
ran
s f
at
per
100 g
to
tal
fat)
28
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• The results showed significantly higher levels of
trans fats in the bodies of the heart attack patients.
• You would do well to read nutrition labels and
avoid trans fats as much as possible in your own
diet.
The Process of Science:
Are Trans Fats Bad for You?
© 2013 Pearson Education, Inc.
83 Theories in Science
• What is a scientific theory, and how is it different
from a hypothesis?
– A scientific theory is much broader in scope than a
hypothesis.
– Theories only become widely accepted in science if
they are supported by an accumulation of extensive
and varied evidence.
© 2013 Pearson Education, Inc.
84 Theories in Science
• Scientific theories are not the only way of “knowing nature.”
• Science, religion, and art are very different ways of trying to make sense of nature.
© 2013 Pearson Education, Inc.
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85 The Culture of Science
• Scientists build on what has been learned from
earlier research.
– They pay close attention to contemporary
scientists working on the same problem.
• Cooperation and competition characterize the
scientific culture.
– Scientists check the conclusions of others by
attempting to repeat experiments.
– Scientists are generally skeptics.
© 2013 Pearson Education, Inc.
86 Science, Technology, and Society
• Science and technology are interdependent.
– New technologies advance science.
– Scientific discoveries lead to new technologies.
– For example, the discovery of the structure of
DNA about 60 years ago led to a variety of DNA
technologies.
© 2013 Pearson Education, Inc.
87 Figure 1.17
30
88
• Science has two key features that distinguish it
from other forms of inquiry. Science
– depends on observations and measurements that
others can verify and
– requires that ideas (hypotheses) are testable by
experiments that others can repeat.
The Culture of Science
© 2013 Pearson Education, Inc.
89 Figure 1.18
90
– Technology has improved our standard of living
in many ways, but it is a double-edged sword.
– Technology that keeps people healthier has
enabled the human population to double to
7 billion in just the past 40 years.
– The environmental consequences of this
population growth may be devastating.
Science, Technology, and Society
© 2013 Pearson Education, Inc.
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91 Evolution Connection:
Evolution in Our Everyday Lives
• Antibiotics are drugs that help cure bacterial
infections.
• When an antibiotic is taken, most bacteria are
typically killed.
• Those bacteria most naturally resistant to the drug
can still survive.
• Those few resistant bacteria can soon multiply and
become the norm and not the exception.
© 2013 Pearson Education, Inc.
92
• The evolution of antibiotic-resistant bacteria is a
huge problem in public health.
• Antibiotics are being used more selectively.
• Many farmers are reducing the use of antibiotics in
animal feed.
Evolution Connection:
Evolution in Our Everyday Lives
© 2013 Pearson Education, Inc.
93
• It is important to note that the adaptation of
bacteria to an environment containing an antibiotic
does not mean that the drug created the antibiotic
resistance. Instead, the environment screened the
heritable variations that already existed among the
existing bacteria.
Evolution Connection:
Evolution in Our Everyday Lives
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94 Figure 1.19
Co
lori
ze
d S
EM