CELLS:
AN INTERACTIVE EXPLORATION
Teacher’s Guide
INTRODUCTION
This Teacher’s Guide provides information to help you get the most out of Cells: An Interactive
Exploration. The contents in this guide will allow you to prepare your students before using the
program and present follow-up activities to reinforce the program’s key learning points.
In this virtual journey through the cell, viewers become familiar with cells and their properties.
The program describes and shows examples of cells of many shapes and sizes, and explores the
structure and functions of different types of cells. Eukaryotes and prokaryotes are defined, and
plant and animal cells are compared. Students take a closer look at important organelles such as
mitochondria and chloroplasts, and the roles they play in cell metabolism. They also learn about
proteins, amino acids, ribosomes, DNA, RNA, genes, chromosomes, transcription, and translation. This program also examines three main activities of the cell: energy storage and release,
protein synthesis, and cell reproduction. Examples of specialized cells and their functions are provided, and the effects of viruses, bacteria, disease, and mutations are also explored.
LEARNING OBJECTIVES
After viewing the program, students will be able to:
■ State that all living organisms are comprised of one or more cells.
■ Describe the structures and functions that are common to all cells and identify the differences
between various types of cells.
■ Explain the functions of common cell organelles.
■ Identify the various types of single-cell organisms and their traits.
■ Name the basic parts and functions of DNA and RNA.
■ Identify and describe the stages of meiosis and mitosis.
EDUCATIONAL STANDARDS
NATIONAL STANDARDS
This program correlates with the National Science Education Standards from the National
Academy of Sciences and the Project 2061 Benchmarks for Science Literacy by the American
Association for the Advancement of Science. The content has been aligned with the following
educational standards and benchmarks from these organizations.
■ Science as Inquiry: As a result of activities in grades 9-12, all students should develop abilities
necessary to do scientific inquiry, and understandings about scientific inquiry.
■ Life Science: As a result of their activities in grades 9-12, all students should develop understanding of the cell, molecular basis of heredity, biological evolution, interdependence of
organisms, matter, energy, and organization in living systems, and behavior of organisms.
Reprinted with permission from National Science Education Standards ©1999 by the National Academy of Sciences,
courtesy of the National Academies Press, Washington, D.C.
English Language Arts Standards
The activities in this Teacher’s Guide were created in compliance with the National Standards for
the English Language Arts from the National Council of Teachers of English.
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Copyright © 2005 Cambridge Educational®
■ Students apply a wide range of strategies to comprehend, interpret, evaluate, and appreciate
texts. They draw on their prior experience, their interactions with other readers and writers,
their knowledge of word meaning and of other texts, their word identification strategies, and
their understanding of textual features (e.g., sound-letter correspondence, sentence structure,
context, graphics).
■ Students adjust their use of spoken, written, and visual language (e.g., conventions, style,
vocabulary) to communicate effectively with a variety of audiences and for different purposes.
■ Students employ a wide range of strategies as they write and use different writing process
elements appropriately to communicate with different audiences for a variety of purposes.
■ Students apply knowledge of language structure, language conventions (e.g. spelling and
punctuation), media techniques, figurative language, and genre to create, critique, and discuss print and nonprint texts.
■ Students conduct research on issues and interests by generating ideas and questions, and by
posing problems. They gather, evaluate, and synthesize data from a variety of sources (e.g.,
print and nonprint texts, artifacts, people) to communicate their discoveries in ways that suit
their purpose and audience.
■ Students use a variety of technological and information resources (e.g., libraries, databases,
computer networks, video) to gather and synthesize information and to create and communicate knowledge.
■ Students use spoken, written, and visual language to accomplish their own purposes (e.g., for
learning, enjoyment, persuasion, and the exchange of information).
Standards for the English Language Arts, by the International Reading Association and the National Council of
Teachers of English, copyright 1996 by the International Reading Association and the National Council of Teachers of
English. Reprinted with permission.
Technology Standards
The activities in this Teacher’s Guide were created in compliance with the following National
Education Technology Standards from the National Education Technology Standards Project.
■ Basic operations and concepts: Students demonstrate a sound understanding of the nature
and operation of technology systems.
■ Basic operations and concepts: Students are proficient in the use of technology.
■ Technology productivity tools: Students use technology tools to enhance learning, increase
productivity, and promote creativity.
■ Technology productivity tools: Students use productivity tools to collaborate in constructing
technology-enhanced models, prepare publications, and produce other creative works.
■ Technology communication tools: Students use a variety of media and formats to communicate information and ideas effectively to multiple audiences.
■ Technology communication tools: Students use telecommunications to collaborate, publish,
and interact with peers, experts, and other audiences.
■ Technology research tools: Students use technology to locate, evaluate, and collect information from a variety of sources.
■ Technology problem-solving and decision-making tools: Students use technology resources for
solving problems and making informed decisions.
The National Education Technology Standards reprinted with permission from the International Society of Technology
Education.
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PROGRAM OVERVIEW
In Cells: An Interactive Exploration, students discover the many types, sizes, shapes, functions,
and components of cells. They realize that while humans and other animals are made of millions
of cells, some living things are composed of just one cell. Through engaging animations and
revealing text, students distinguish between different cell types, and explore the structures and
functions of each. They examine the vital parts of the nucleus, as well as the processes of homeostasis, protein synthesis, cellular respiration, and photosynthesis. Cells: An Interactive Exploration
also introduces students to the various roles of cells and some of the many ways in which they
work together, and it discusses the unfortunate health consequences of cell invasions and mutations, including HIV and other viruses, infections, and cancer.
MAIN TOPICS
Topic 1: What is a Cell?
The program begins with an overview of the basics of cell biology, including their many sizes and
shapes, and the fact that some organisms consist of only a single cell while others are made of
millions of cells.
Topic 2: Cell Types
This section explains the difference between eukaryotes and prokaryotes, and provides examples
of each.
Topic 3: Cell Structure and Organelles
This section brings the user inside two basic types of cells: plant cells and animal cells. Here,
structures common to all cells are made clear, while organelles unique to each type are highlighted. The important components of the nucleus are introduced.
Topic 4: Cell Functions
This section begins with an explanation of homeostasis, and then expands into an explanation of
three basic functions of the cell. The role of DNA, RNA, and ribosomes in protein synthesis is
described in detail. The processes and relationship between cellular respiration and photosynthesis is made clear, and cellular reproduction is examined in both single-celled and multicellular
organisms.
Topic 5: Cells Working Together
This section makes the connection between functions within the cell and functions of the organ
and organism. Examples of some of the unique properties of specific types of cells provide a “big
picture” perspective on the important roles of cells.
Topic 6: Cell Invasion and Mutation
The section explores health issues related to cell afflictions. Viruses (including HIV), bacterial
infections, cancer, and genetic mutations are overviewed.
FAST FACTS
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■ The eggs laid by the extinct Elephant Bird were the largest single cells to have ever existed on
Earth. Larger than the largest dinosaur eggs, they measured up to 13 inches (33 cm) in length
and held a liquid content estimated at two gallons (7.5 liters).
■ A methanogen is a methane-producing form of Archaea. Archaea are similar to bacteria in
many ways, but also perform some eukaryotic-like processes such as protein synthesis. The
presence of Archaea is one possible explanation for the recent discovery of methane on Mars.
■ The number of beneficial bacteria in the human intestine is about equal to the number of
cells in the human body.
■ There are over two hundred different types of cells in the human body.
■ Both mitochondria and chloroplasts contain DNA fragments. According to the endosymbiotic
theory, these micro machines, and possibly other cell organelles, evolved from symbiotic relationships between early prokaryotic life forms.
■ The DNA code in all of the mitochondria in your cells came only from your mother. They can
be traced back to your grandmother and your grandmother’s mother. Mitochondrial DNA, or
mtDNA, has been used to help track lineage and identify the true parents of children separated from their families by war.
■ Lysosomes are responsible for the loss of a tadpole’s tail during metamorphosis. They digest
the tail and make the materials used to construct parts of the new frog.
■ Wood and cork are the dead cellulose cell walls of trees. Paper is often made of broken down
wood fibers. Cotton is also cellulose fibers.
■ 300 million cells in the human body die and are replaced (most of them) every minute.
■ Given the right conditions (nutrients, pH temperature, etc.), bacteria cells replicate about
every twenty minutes. Cell division only slows or stops if conditions change or nutrients run
out.
■ The more specialized a cell becomes, the less likely it is to divide. Neurons and muscle cells
stop dividing in early childhood.
■ Chromosomes carried by the male sperm determine whether an embryo will develop into a
male or female organism.
■ Many antibiotics taken for an infection can cause stomach pain. This is because the antibiotics kill off the beneficial bacteria along with the infectious ones. Without the bacteria to
assist us in the digestion of our food, we experience discomfort. Foods that contain active cultures, such as acidophilus commonly found in yogurt, can help replenish the good bacteria
killed by an antibiotic and decrease digestive pains.
■ Researchers are working on cancer vaccines that would work by teaching the body’s immune
system to identify and destroy cancer cells.
VOCABULARY TERMS
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amino acid: The building block of proteins, containing an amino group and a carboxylic acid
group.
ATP (adenosine triphosphate): A molecule that is used to produce energy for an organism.
Made by the mitochondria within the cell.
bacteria: The smallest of microscopic organisms. Abundant in nature, they multiply rapidly.
Certain species are active agents in fermentation, while others are the cause of certain infectious
diseases.
cell: The fundamental unit that makes up all organisms on earth.
cell membrane: Also called the plasma membrane. The cell membrane regulates the flow of
materials into and out of the cell.
cell wall: Rigid structure surrounding the cell membrane of plant cells. It acts as a “skeletal system” for the cell by giving it support. Found in various forms in all kingdoms of organisms
except animalia.
chloroplasts: Organelles that perform photosynthesis by taking in sunlight, water, and carbon
dioxide to make oxygen and sugar (a form of food). Also contain a green pigment called chlorophyll, which gives plants a green color.
chromosomes: Long thread-like bodies composed of DNA and protein, found in the nucleus of
eukaryotic cells. They contain the genes that contain the code for all the organism’s proteins.
cytoskeleton: The transparent network of protein filaments that maintains the cell’s shape,
holds organelles in place, and moves parts of the cell around if needed.
DNA: Deoxyribonucleic acid; the chemical that makes up all genes, and therefore chromosomes.
endoplasmic reticulum (ER): A folded membrane that moves materials around in the cell.
eukaryotic cell: A cell with a nucleus and other organelles with membranes around them.
Animal, plant, fungi, and protista cells are eukaryotic.
gene: The specific area of a chromosome that contains the code for one protein. In some
organisms there are two of each gene—one from each parent.
glucose: A monosaccharide sugar, C6H12O6, occurring widely in most plant and animal tissue.
It is the principal circulating sugar in the blood and the major energy source of the body.
golgi body (golgi apparatus): An organelle that moves proteins to the outside of the cell.
homeostasis: The process by which the body controls and regulates the environment within
cells.
lysosome: Contains enzymes that digest waste and worn out cell parts.
microbe: A minute, single-cell life form; a microorganism.
mitochondria: Organelles that break down food molecules to produce energy.
mitosis: The process in cell division by which the nucleus divides, typically consisting of four
stages (prophase, metaphase, anaphase, and telophase), and normally resulting in two new
nuclei, each of which contains a complete copy of the parental chromosomes. Also called
karyokinesis.
nucleus: Control center of the cell where DNA is stored.
organelle: Any one of the specialized structures within the cell that performs a function for the cell.
osmosis: The process by which cells can gain or lose water.
photosynthesis: The process in green plants and certain other organisms by which carbohydrates are synthesized from carbon dioxide and water using light as an energy source. Most
forms of photosynthesis release oxygen as a byproduct.
plant: An organism that uses photosynthesis to produce its own food. Its cells contain cellulose
and a cell wall.
prokaryotic cell: A cell that does not have a nucleus or organelles with membranes around
them. Bacteria are examples of prokaryotic cells.
RNA: Ribonucleic acid; the chemical that copies the information from the DNA and carries it to
the ribosomes to be translated into protein.
ribosome: The site of protein synthesis, where mRNA is translated into protein.
vacuole: A cavity in the cell’s cytoplasm that stores water, food, pigments, waste, or other
materials. Vacuoles are large in plant cells and small in animal cells.
virus: A submicroscopic parasite that cannot live on its own, but uses another cell’s machinery
to reproduce.
PRE-PROGRAM DISCUSSION QUESTIONS
1.
2.
3.
4.
5.
6.
7.
How big is a cell?
In what ways do various cells differ from each other?
What functions do cells perform?
In what ways do cells work together?
What is RNA, and how is it different from DNA?
What causes a cell to die?
Why is it valuable to study the structure, functions, and relationships of cells?
POST-PROGRAM DISCUSSION QUESTIONS
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1. What do enzymes and hormones do for cells?
2. Name some characteristics of organisms that are not genetically determined.
3. How do cells react to a lack of water or oxygen? Do all cells need water and oxygen?
4. Cell organelles perform many different functions. What happens if an organelle does not
function correctly? Consider organelles such as mitochondria, chloroplasts, ribosomes, etc.
5. According to Charles Darwin’s Theory of Evolution, the vast and diverse number of living
species living on earth today can be attributed to mutation, adaptation, and survival of the
fittest. What evidence can we see in the natural world that supports this theory?
GROUP ACTIVITIES
All That Work for a Piece Of Toast!
This activity can be conducted as a homework assignment or carried out in the classroom in
small groups with a few toasters, a loaf of bread, and butter.
Cells work together to form tissues that work together as organs. The human body employs ten
major organ systems to do the everyday work required to maintain and operate the body. These
complex systems mostly go unnoticed throughout the day. Explore how these organ systems
work together as an organism—the human body.
Go through the steps of making and eating a piece of toast. To gain an understanding and
appreciation for how your organ systems work so seamlessly, stop and make notes along the
way. Break down each step of the process and identify which organ systems are called into
action to complete each step.
Life in the Water
Work in small groups to collect samples from ponds, streams, and other water sources in your
area. Examine each water sample under a microscope (use more than one type of microscope, if
available). Sketch examples of any organisms that are visible. In what ways are they the same?
How do they differ? Are any organelles visible?
Cell Reproduction
Scientists say that yeast cells need sugar (food/energy), water, and warmth to reproduce. How
true is this statement? Divide the class into small groups and have each group conceive and conduct an experiment to see if the scientists are entirely correct. Each group should record their
hypothesis and their results in a one-page essay.
INDIVIDUAL STUDENT PROJECTS
The Future of Medicine
Research the current findings of the Human Genome Project. What are the main objectives of
this project? What information has been established? How can this information benefit modern
medicine? Develop a futuristic, hypothetical therapy or treatment based on the discovery and
mapping of a specific gene.
Protein Supplements
Use the Internet or library to get a list of the twenty essential amino acids that the human body
needs to create proteins. Then, visit a local pharmacy or health food store to see how many different types of amino acids are available. What do the labels claim these supplements do?
Return to the library or Internet to see if you can find any research or studies that have been
done on the effectiveness of these supplements.
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INTERNET ACTIVITIES
Morality and Ethics in Scientific Research
Use the Internet to investigate current events or research regarding cell reproduction, such as
reproductive or therapeutic cloning, gene therapy, genetic engineering, etc. Present your findings
to the class in an oral presentation and one-page summary report. Then, conduct a group debate
on the issue in order to explore the pros and cons of the technology. What good might come
out of it? What adverse effects are possible? What moral and/or religious beliefs conflict with or
support this technology?
Understanding Genetics
Use the Internet or the library to learn about and explore the principles of Mendelian genetics.
Highlight the principles of heredity by charting the physical traits of your parents, grandparents,
and other relatives. Which traits are dominant? Which are recessive? Which characteristics
appear to be inherited, and which seem to be acquired?
ASSESSMENT QUESTIONS
Q: ____________ are single celled organisms.
(a) Prokaryotes
(b) Eukaryotes
(c) Both prokaryotes and eukaryotes
(d) Neither prokaryotes or eukaryotes
A: (c)
Feedback: All prokaryotes are single-celled organisms. Some eukaryotes are also single-celled.
Q: Eukaryotes do not contain a nucleus or membrane-bound organelles. (True of False)
A: False
Feedback: Prokaryotes do not contain a nucleus or membrane-bound organelles.
Q: Prokaryotes reproduce through a process called ____________.
(a) mitosis
(b) synthesis
(c) meiosis
(d) binary fission
A: (d)
Feedback: Prokaryotes reproduce asexually through a process called “binary fission.”
Q: Which of the following is found in an animal cell?
(a) Vacuole
(b) Cell wall
(c) Chloroplast
(d) Chlorophyll
A: (a)
Feedback: Both plant and animal cells contain vacuoles, but those found in animal cells are
smaller than those found in plant cells.
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Q: The double helix structure of the DNA molecule uncoils in both DNA replication and during
protein synthesis. (True of False)
A: True
Feedback: During cellular reproduction, the DNA molecule uncoils in order to replicate. DNA
also uncoils during the transcription phase of protein synthesis, allowing mRNA to copy a portion
of its genetic sequence.
Q: Energy storage and release are carried out by what two organelles?
(a) The nucleus and ribosomes
(b) Mitochondria and chloroplasts
(c) Centrosomes and lysosomes
(d) Vacuoles and golgi bodies
A: (b)
Feedback: Cellular respiration occurs in the mitochondria; photosynthesis occurs In chloroplasts.
Q: Most eukaryotic cells replicate through a process called mitosis whereby a diploid parent cell
divides into _____________ daughter cells.
(a) four haploid
(b) four diploid
(c) two diploid
(d) two haploid
A: (c)
Feedback: Mitosis is the process by which a diploid parent cell, containing two sets of chromosomes, divides into two new diploid daughter cells, each containing a full set of chromosomes
identical to those of the parent.
Q: Viruses are not classified as cells. (True or False)
A: True
Feedback: Viruses are not classified as cells, or even living organisms, because they are dependent upon a host cell in order to reproduce.
Q: The process by which the body controls and regulates the environment within its cells is called
_____________.
(a) cellular respiration
(b) osmosis
(c) protein synthesis
(d) homeostasis
A: (d)
Feedback: Homeostasis controls temperature regulation, blood glucose levels, and maintenance
of water content, and is maintained by a variety of negative feedback mechanisms.
Q: _____________ are produced through a process called meiosis.
(a) Prokaryotes
(b) Gametes
(c) Myocytes
(d) Neurons
A: (b)
Feedback: In animals, female eggs and male sperm cells, called gametes, are formed through a
special type of cell division called meiosis. These gametes fuse together during sexual reproduction to form a zygote which grows into a new organism.
ADDITIONAL RESOURCES
WEB SITES
Cells alive!
www.cellsalive.com
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The Virtual Library of Biochemistry and Cell Biology
http://bcb.vlib.org
The Biology Project from the University of Arizona
www.biology.arizona.edu
Structure and Function in Cell Biology
http://darwin.nmsu.edu/~molbio/cell/Page1.html
The Franklin Institute Online: Living Things
www.fi.edu/tfi/units/life
Basic Principles of Genetics: An Introduction to Mendelian Genetics
http://anthro.palomar.edu/mendel/default.htm
Human Genome Project Information
www.ornl.gov/TechResources/Human_Genome/home.html
Biology Online
www.biology-online.org
BOOKS
Exploring The Way Life Works: The Science of Biology, by Mahlon B. Hoagland, Bert Dodson,
Judith Hauck. ISBN: 076371688x, Jones & Bartlett Pub., 2001
The Cartoon Guide To Genetics, by Larry Gonick, Mark Wheelis (contributor). ISBN: 0062730991,
Harper Perennial, 1991
Other End of the Microscope: The Bacteria Tell Their Own Story, a Fantasy, by Bert Dodson (illustrator), Eleanor S. Tupper (editor), Elmer W. Koneman. ISBN: 1555812279, American Society for
Microbiology, 2002
OTHER PRODUCTS
Journey Through the Cell Part 1—Cells: An Introduction, VHS/ DVD, Cambridge Educational
In this virtual journey through the cell, viewers become familiar with cells and their properties.
The program describes and shows examples of cells of many shapes and sizes, and explores the
structure and functions of different types of cells. Eukaryotes and prokaryotes are defined, and
plant and animal cells are compared. Emphasizing cells as the basic building blocks of all organisms, this segment describes the organization of cells and the formation of tissues, organs and
systems. Part 1 concludes with an overview of the organelles and their functions. A Cambridge
Educational Production.
Item no: 8229, www.films.com, 1-800-257-5126
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Journey Through the Cell Part 2—Cell Functions: A Closer Look, VHS/DVD, Cambridge Educational
This program examines three main activities of the cell: energy storage and release, protein synthesis, and cell reproduction. Students take a closer look at important organelles such as mitochondria and chloroplasts and the roles they play in cell metabolism. They also learn about proteins, amino acids, ribosomes, DNA, RNA, genes, chromosomes, transcription, and translation.
Mitosis is clearly defined and illustrated. The program is divided into three distinct segments, so
that teachers can easily pause to review key concepts or show the video in three separate class
periods. A Cambridge Educational Production.
Item no: 8230, www.films.com, 1-800-257-5126
Cells: The Basic Unit of Life S.M.A.R.T. Box , VHS/DVD, CD-ROM, Posters, Teacher’s Guide,
Resource Pack; CURRICULUM MEDIA GROUP
The Cells S.M.A.R.T. Box provides teachers and students with an outstanding blend of multimedia materials designed to support Life Science and Biology programs. Correlated to the National
Academies of Science educational standards, the S.M.A.R.T. Box combines core content, creative
activities to test comprehension, a Teacher’s Guide, and a Teacher’s Resource Pack with suggested
lesson plans to deliver an enriching and engaging learning experience.
Basic cell structures and functions, the formation of tissue, and the function of organs and organ
systems are authoritatively covered. The Cells S.M.A.R.T. Box will energize your classroom with a
comprehensive, research-based multimedia approach to cell structure and function that provides
a balanced mix of videos, CD-ROMs, and posters to support your Biology curriculum. One multimedia set. © 2003.
The Cells S.M.A.R.T. Box contains:
3 video programs:
• Cells—An Introduction (VHS or DVD-R)
• Cell Functions—A Closer Look (VHS or DVD-R)
• Voyage Inside the Cell (VHS or DVD-R)
• Cell City (CD-ROM)
10 laminated posters:
• Plant Cells • Cell Shapes and Sizes • Organelles • Mitosis • Meiosis • DNA • Human Cells •
Cell Organization • Cell Membranes • Bacteria
Teacher’s Guide packed with information: a curriculum map, lesson plans, educational standards, fast facts, program overviews, learning objectives, vocabulary terms, discussion questions,
Web site resources, student activities, and a reading list
Teacher’s Resource Pack of reproducible hand-outs that include student activities and a timeline
of biotechnology history
Item no: 31358, www.films.com, 1-800-257-5126
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For information on other programs
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