PowerLecture:
Chapter 1
Learning About
Human Biology
Learning Objectives
 List
features that distinguish living organisms
from nonliving matter.
 Describe the general pattern of energy flow
through Earth’s life forms, and explain how
Earth’s resources are used again and again
(cycled).
 Explain the interdependency that exists
among organisms.
 List the steps of the scientific method of
inquiry and use an example to illustrate.
Learning Objectives (cont’d)
 Define
the word “theory” as correctly used in
science.
 Understand as well as you can what
limitations are imposed on science and
scientists.
 Explain the importance of alternative
hypotheses and control groups in scientific
experimentation.
Impacts/Issues
What Kind of World Do
We Live In?
What Kind of World Do We Live In?
Current world events seem chaotic.




Infectious diseases such as
“bird flu” pose global threats.
Natural disasters cause
widespread devastation.
Human activities greatly affect
our environment.
What Kind of World Do We Live In?
Despite the chaos, we have tools available
to help us meet these challenges.



Systematic observation allows us to ask
questions and find answers.
Scientific investigation helps us to understand
our place in the world.
Useful References for Impacts/Issues
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 U.S.
EPA: Global Warming Site
 InfoTrac: The Great Plague. Rene Skelton.
National Geographic World, Mar. 1999.
 InfoTrac: Avian Flu: Why All the Squawk?
Linda S. Nield. Consultant, Feb. 1, 2006.
How Would You Vote?
To conduct an instant in-class survey using a classroom response
system, access the “JoinIn Clicker Content” from the PowerLecture main
menu.
 Should
the United States provide funding to
help preserve the reefs?


a. Yes: Without readily available green products
and services, converting to a sustainable society
is unrealistic.
b. Not entirely: I'm doing what I can to improve
sustainability, including recycling and using less
energy.
Useful References for
How Would You Vote?
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 InfoTrac:
Should the Arabian (Persian) Gulf
become a marine sanctuary? Oceanus, Fall
1993 v36 n3 p53(10).
 NCDC: Regional Perspectives: Seas of the
Middle East
Section 1
The Characteristics of
Life
The Characteristics of Life

Living and nonliving things
share common characteristics,
such as being composed of
atoms, the smallest units of
natural substances.
The Characteristics of Life
Living things, though, have many distinctive
features:






Living things take in and use
energy and materials.
Living things sense and respond
to specific changes in their
environment.
Living things reproduce and grow.
Living things consist of one or more cells.
Living things maintain homeostasis (dynamic
balance).
Figure 1.1
Useful References for Section 1
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 PBS:
DNA
 InfoTrac: The Meaning of Life. Lin Chao.
BioScience, Mar. 2000.
 InfoTrac: The Mystery of Life. Carl Sagan.
UNESCO Courier, Sept. 1984.
Section 2
Our Place in
the Natural World
Our Place in the Natural World
Humans have evolved over time.



Human beings are a
part of biological
evolution—the change
in organisms through
the generations.
Humans are mammals
belonging to the animal
kingdom, one of the four
kingdoms of life in the domain Eukarya.
Figure 1.2
Our Place in the Natural World
Humans are related to all other
organisms—and humans also have some
distinctive features.



Humans share characteristics
with our closest primate
relatives.
Humans also have distinctive
features: increased dexterity,
large brain, analytical skills,
sophisticated communication,
and culture.
Figure 1.3
Video: Earliest Homo Sapiens
 This
video clip is available in CNN Today
Videos for Biology, 2004, Volume VIII.
Instructors, contact your local sales
representative to order this volume, while
supplies last.
Useful References for Section 2
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 InfoTrac:
The Human Genus. Bernard Wood,
Mark Collard. Science, April 2, 1999.
 InfoTrac: A Tale Told by DNA. Nell Boyce.
U.S. News & World Report, Dec. 16, 2002.
Section 3
Life’s Organization
Life’s Organization
Life is organized on many levels.




Atoms and molecules are nonliving materials
from which all of nature is built.
Cells are organized into increasingly complex
levels: tissues >>> organs >>> organ systems
>>> organisms.
Organisms, in turn, form populations >>>
communities >>> ecosystems >>> biosphere.
Levels of Organization in Nature
Figure 1.4
Fig. 1.4, p. 4-5
Fig. 1.4, p. 4-5
Life’s Organization
Organisms are connected through the flow
of energy and cycling of materials.


Energy flows from the sun.
•
•
•

Plants (“producers”) trap this energy by
photosynthesis.
Animals (“consumers”) feed on the stored energy in
plants, using cellular respiration.
Bacteria and fungi (“decomposers”) break down the
biological molecules of other organisms in order to
recycle raw materials.
All organisms are part of webs that depend on
one another for energy and raw materials.
Flow of Energy and Cycling of Materials in
the Biosphere
Figure 1.5
Video: Biodiversity
 This
video clip is available in CNN Today
Videos for Environmental Science, 2003,
Volume VI. Instructors, contact your local
sales representative to order this volume,
while supplies last.
Useful References for Section 3
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 Ecological
Society of America
 InfoTrac: Lost at Sea: Coral Reefs,
Considered the ‘Rainforests’ of the Marine
World, Now Have Even More in Common
with Those Fragile Ecosystems. Scott
Kirkwood. National Parks, Spring 2006.
Section 4
Science Is a Way of
Learning about the
Natural World
Science Is a Way of Learning about the
Natural World
Science is an approach to gathering
knowledge.


Biology, like all science, pursues a methodical
search for information that reveals the secrets
of the natural world.
Figure 1.6
Science Is a Way of Learning about the
Natural World

Explanations are sought using an approach
known as the scientific method:
• Observe some aspect of the natural world and ask a
question.
• Develop hypotheses (educated guesses) using all
known information.
• Predict what the outcome would be if the hypothesis is
valid.
• Test the hypothesis by experiments, models, and
observations.
• Repeat the tests for consistency.
• Analyze and report objectively on the tests and
conclusions.
Fig. 1.7b, p. 7
Hypothesis
Olestra® causes intestinal cramps.
Prediction
People who eat potato chips made with Olestra will be
more likely to get intestinal cramps than those who eat
potato chips made without Olestra.
Experiment
Control Group
Eats regular
potato chips
Results
93 of 529 people 89 of 563 people
get cramps later get cramps later
(17.6%)
(15.8%)
Experimental Group
Eats Olestra
potato chips
Conclusion
Percentages are about equal. People who eat potato
chips made with Olestra are just as likely to get intestinal
cramps as those who eat potato chips made without
Olestra. These results do not support the hypothesis.
Stepped Art
Fig. 1.7b, p. 7
Science Is a Way of Learning about the
Natural World
Experiments are major scientific tools.


Experiments involve tests in which conditions
are carefully controlled.
•
•

Control groups are used to identify side effects
during a test that involves an experimental group.
The experimental group experiences all of the same
conditions as the control except for the variable
being studied.
The sample size must be large enough to be
representative of the whole.
Sampling Error
Figure 1.12
Science Is a Way of Learning about the
Natural World
Science is an ongoing enterprise.



Single experiments rarely provide concrete
answers.
Not all science is performed by conducting
experiments.
Useful References for Section 4
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.



National Health Museum: Discovery, Chance, and the
Scientific Method
InfoTrac: Water Saver: Could a Population Boom Cause
a Decline in One Bay’s Water Quality? Mona Chiang.
Science World, Sept. 19, 2005.
InfoTrac: The Real Method of Scientific Discovery
…Often Involves a Creative, Imaginative Leap. Burton
S. Guttman. Skeptical Inquirer, Jan.–Feb. 2004.
Section 5
Cancer, Broccoli, and
Mighty Mice
Cancer, Broccoli, and Mighty Mice
 Researchers
discovered that sulforaphane in
broccoli could reduce cancers in mice.
 However, they also learned that the body’s
own defenses play a vital role.
Figure 1.8
Useful References for Section 5
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 Cancer
Research Institute: Cervical Cancer
Vaccine Approved
 InfoTrac: My Life as a Guinea Pig: Clinical
Trials Are Inherently Risky, But One Saved
Me. Jamie Reno. Newsweek, Aug. 6, 2001.
 InfoTrac: Anti-cancer Veggies. Natural Life,
May–June 2006.
Section 6
Science in Perspective
Science in Perspective
A scientific theory explains a large number
of observations.





A theory is a related set of hypotheses that
form a broad-ranging explanation of many
phenomena.
Theories are accepted or rejected on the basis
of tests and are subject to revision.
Scientists must be content with relative
certainty, which becomes stronger as more
repetitions are made.
Scientists must be prepared to change their
minds in light of new evidence.
Science in Perspective
 Science


has limits.
Science is limited to questions that can be tested;
subjective questions do not readily lend
themselves to scientific analysis or experiments.
Science has the potential to
be used for controversial
endeavors, which means that
all of society must commit to
responsible use of scientific
knowledge.
Figure 1.9
Fig. 1.9b, p. 9
Video: Smog Pollution
 This
video clip is available in CNN Today
Videos for Environmental Science, 2004,
Volume VII. Instructors, contact your local
sales representative to order this volume,
while supplies last.
Useful References for Section 6
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.



American Journal of Bioethics
PBS: NOVA—The Stem Cell Debate
InfoTrac: Scientists at War. Leif J. Robinson.
Odyssey, Feb. 2002.
 InfoTrac: Above All, Do No Harm. Stephen Jay
Gould. Natural History, Oct. 1998.
 InfoTrac: Bioethics and the Stem Cell Research
Debate. Robyn S. Shapiro. Social Education, May–
June 2006.
Section 7
Critical Thinking in
Science and Life
Critical Thinking in Science and Life
Critical thinking is an objective evaluation
of information.
Consider the source.




Let credible scientific evidence, not opinions or
hearsay, do the convincing.
Question credentials and motives.
Evaluate the content.



Be able to distinguish between
cause and correlation.
Separate facts from opinions.
Figure 1.10
Useful References for Section 7
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 Scientific American:
Smart People Believe
Weird Things
 InfoTrac: Question Authority: Kids Need to Be
Skeptical of the Curriculum. It’s the Only Way
to Develop a Balanced View of the World.
Glenn DeVoogd. School Library Journal, April
2006.
Section 8
Are Herbal Supplements
Safe?
Are Herbal Supplements Safe?
Controversy surrounds the use of herbal
supplements.




Some supplements have
been linked to harm in
humans.
Other supplements have
been shown to offer no
biologically observed effect.
Rigorous testing of supplements is currently
being undertaken by the National Institute of
Health and others.
Figure 1.11
Video: Ephedra Dangers
 This
video clip is available in CNN Today
Videos for Biology, 2003, Volume VII.
Instructors, contact your local sales
representative to order this volume, while
supplies last.
Useful References for Section 8
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 U.S.
FDA: Dietary Supplements
 InfoTrac: Any Science Behind the Hype of
‘Natural’ Dietary Supplements? Teri Capriotti.
Dermatology Nursing, Oct. 2005.
 InfoTrac: Ephedra/Ephedrine Dangers. David
Nicklin. Patient Care for the Nurse
Practitioner, June 2003.