A JOURNEY THROUGH THE CELL
PART ONE—CELLS:
AN INTRODUCTION
Teacher’s Guide
INTRODUCTION
This Teacher’s Guide provides information to help you get the most out of A Journey Through
the Cell: Part One—Cells: An Introduction. 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 video program, students become familiar with the basic structure of cells. Examples of
many different shapes and sizes of cells are presented with an overview of the structures and
functions of different types of cells. Emphasizing cells as the basic building blocks of all organisms, the program describes the organization of cells and the formation of tissues, organs, and
systems. The program concludes with an overview of the organelles and their functions.
LEARNING OBJECTIVES
After viewing the program, students will…
■ Understand that all living organisms are composed 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 differences between plant and animal cells.
■ Understand that cells are organized into tissue, which in turn functions as an organ in an
organ system.
EDUCATIONAL STANDARDS
National Standards
This program correlates with the National Science Education Standards developed by the National
Academy of Sciences and Project 2061 Benchmarks for Science Literacy from the American
Association for the Advancement of Science. The content has been aligned with the following
educational standards and benchmarks from these organizations.
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Understand the behavior of organisms.
Understand the diversity and adaptations of organisms.
Understand matter, energy, and organization in living systems.
Understand molecular basis of heredity.
Understand structure and function in living systems.
Understand the cell.
Understand that all living things are composed of cells, from just one to many millions, whose
details usually are visible only through a microscope. Different body tissues and organs are
made up of different kinds of cells. The cells in similar tissues and organs in other animals are
similar to those in human beings, but differ somewhat from cells found in plants.
■ Understand that the genetic information encoded in DNA molecules provides instructions for
assembling protein molecules. The code used is virtually the same for all life forms. Before a
cell divides, the instructions are duplicated so that each of the two new cells gets all the necessary information for carrying on.
■ Understand that complex interactions among the different kinds of molecules in the cell cause
distinct cycles of activities, such as growth and division. Cell behavior can also be affected by
molecules from other parts of the organism or even other organisms.
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Copyright © 2004 Cambridge Educational ®
■ Understand that gene mutation in a cell can result in uncontrolled cell division, called cancer.
Exposure of cells to certain chemicals and radiation increases mutations and thus increases the
chance of cancer.
■ Understand that most cells function best within a narrow range of temperature and acidity. At
very low temperatures, reaction rates are too slow. High temperatures and/or extremes of acidity can irreversibly change the structure of most protein molecules. Even small changes in acidity can alter the molecules and how they interact. Both single cells and multi-cellular organisms
have molecules that help to keep the cell’s acidity within a narrow range.
■ Understand that a living cell is composed of a small number of chemical elements—mainly carbon, hydrogen, nitrogen, oxygen, phosphorous, and sulfur. Carbon atoms can easily bond to
several other carbon atoms in chains and rings to form large and complex molecules.
Reprinted with permission from National Science Education Standards ©1999 by the National Academy of Sciences,
courtesy of the National Academies Press, Washington, D.C.
From BENCHMARKS FOR SCIENCE LITERACY by the American Association for the Advancement of Science, copyright 1993 by the American Association for the Advancement of Science. Used by permission of Oxford University
Press, Inc. Please note: judgments about the alignment of content presented here with the learning goals in BENCHMARKS FOR SCIENCE LITERACY are those of the author and do not represent the opinion or endorsement of the
AAAS or Oxford University Press, Inc.
English Language Arts Standards
The activities in this Teacher’s Guide were created in compliance with the following National
Standards for the English Language Arts from the National Council of Teachers of English.
■ Use spoken, written, and visual language to accomplish their own purposes (e.g., for learning,
enjoyment, persuasion, and the exchange of information).
■ 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.
■ 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.
■ 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.
■ Conduct research on issues and interests by generating ideas and questions, and by posing
problems. Gather, evaluate, and synthesize data from a variety of sources (e.g., print and nonprint texts, artifacts, people) to communicate their discoveries.
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.
■ Proficient in the use of technology.
■ Demonstrate a sound understanding of the nature and operation of technology systems.
■ Use a variety of media and formats to communicate information and ideas effectively to multiple audiences.
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■ Use technology tools to enhance learning, increase productivity, and promote creativity.
■ Use technology to locate, evaluate, and collect information from a variety of sources.
The National Education Technology Standards reprinted with permission from the International Society of Technology
Education.
PROGRAM SUMMARY
This program introduces students to cells and their properties, including the shapes and sizes of
cells, functions of cells, eukaryotes and prokaryotes, the organization of cells, parts of the cell
and their functions, respiration, chromosomes and DNA, plant cells compared to animal cells,
photosynthesis, diversity of life on Earth and the cell as the basic unit of life.
MAIN TOPIC AREAS
Topic 1: Introduction: What are Cells?
The program begins by explaining what a cell—the basic building block of all life—is. Viewers
learn that there are many different types of cells, varying in size, shape, structure, and function.
Topic 2: The Size of Cells
This section provides the student with a concept of how small cells can be (microscopic) in contrast with the largest cells—egg cells.
Topic 3: Cell Types
Here, cells are divided into two types: prokaryotic, or having no nucleus or organelles, and
eukaryotic, having a nucleus and organelles.
Topic 4: Inside the Cell
This section of the program explores the structure of the cell and the function of several of the
internal organelles.
Topic 5: Plant Cells
The program concludes with a discussion of the structure of the plant cell and the importance of
photosynthesis to all living creatures on Earth.
FAST FACTS
■ An average plant cell is about three times larger than an animal cell.
■ The average life span for a stomach cell is two days; a brain cell can live for a lifetime.
■ The adult human body contains about six quarts of blood, while an infant has about one
quart of blood.
■ The unfertilized ostrich egg is the world’s largest cell.
■ The human brain is made up of about one trillion nerve cells.
■ There are as many microbes in a single gram of soil as there are people in all of China.
■ An average person sheds 40 pounds of skin cells over a lifetime.
■ Direct sunlight causes the lysosomes in skin cells to burst. The enzymes released kill the cells of
the epidermis and lead to the blistering and peeling experienced with sunburn.
■ 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.
■ There are over two hundred different types of cells in the human body.
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VOCABULARY TERMS
bacteria: The smallest of microscopic organisms. Abundant in nature, they multiply rapidly.
Certain species are active agents in fermentation, while others appear to be 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: 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.
golgi body (golgi apparatus): Package and move proteins to the outside of the cell.
lysosome: Contains enzymes that digest waste and worn out cell parts.
microbe: A minute, single-cell life form; a microorganism.
microorganism: An organism of microscopic or submicroscopic size.
mitochondria: Organelles where food molecules are broken down and energy is released.
nucleus: Control center of the cell where DNA is stored.
organelle: One of the structures found in the cell, which perform a function of the cell.
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 and other 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 the RNA is translated into protein.
vacuole: Vacuoles store water, food, pigments, waste, or other materials. Vacuoles are large in
plant cells and small in animal cells.
virus: Not classified by a kingdom, a virus cannot “live” on its own, but uses another cell’s
machinery to reproduce.
PRE-PROGRAM DISCUSSION QUESTIONS
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5.
Energy is often defined as the ability to do work. Do cells require energy?
How large are cells?
Do all cells look alike?
Name as many parts of the cell as you can and tell what they do for the cell.
Why is it valuable to study the structure, functions and relationships of cells?
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POST-PROGRAM DISCUSSION QUESTIONS
1. Cell organelles perform many different functions. What happens if an organelle does not
function correctly? Consider organelles such as mitochondria, chloroplasts, ribosomes, etc.
2. Why do different types of cells have different shapes and structures?
3. How does the plant cell use photosynthesis to grow and thrive?
4. Cells work together as organ systems to do work in the body. Which cell organelles perform a
function similar to an organ system in the body?
5. How many different types of cells can you name?
6. The video focuses on the structure of eukaryotic cells. What types of cells are prokaryotic
cells? How do they survive without a nucleus?
GROUP ACTIVITIES
What’s in the Water?
Collect samples from ponds, streams, and other water sources in your area. Work in small groups
to examine each water sample under a microscope. Sketch examples of any organisms that are
visible. How do they differ? In what ways are they the same? Why do you think some samples
have more organisms than others?
Let the Sunshine In
Explore how sunlight affects a plant. Using several types of indoor houseplants, cover portions of
the leaves of each plant with large and small stickers or paper cutouts. Maintain the plants with
sunlight and water over several weeks. Check each plant about once a week to observe and
record any changes in the areas that are blocked from sunlight by the stickers. Is the health of
plant affected overall? How do plants use sunlight in photosynthesis?
INDIVIDUAL STUDENT PROJECTS
What’s in a Cell?
Make a poster showing a typical animal cell and a typical plant cell, with labels.
Growing CO2
Design an experiment to show that seeds produce carbon dioxide (evidence of cell respiration) as
they grow.
INTERNET ACTIVITIES
Genetic Engineering
Investigate current events in genetic engineering. Use the Internet to find out about current
research, political actions, and sociological perspectives. Choose one aspect that is of particular
interest to you and share it with the class through an oral presentation.
Bacteria is Good
Bacteria are often thought of as harmful. Actually, most bacteria are not harmful; they perform
important functions for human beings. In what ways do bacteria help us? Use the Internet to
find out more about ways in which bacteria benefit human life.
Cell Malfunctions
Search the Internet for examples of how external factors (such as the environment, drugs, etc.)
can affect the functioning of cells, either positively or negatively. Identify at least three factors,
and explain how each impacts the cell.
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ASSESSMENT QUESTIONS
Q: All living things on Earth are made of cells. (True or False)
A: True
Feedback: Cells are the building blocks of all life.
Q: Most cells are microscopic. They are measured in units called _________ .
(a) microbes
(b) millimeters
(c) pixels
(d) microns
A: (d)
Feedback: They are measured in units called microns, or micrometers.
Q: Ostrich eggs contain all of the nutrients needed to develop the baby ostrich. (True or False)
A: True
Feedback: Egg cells from animals other than mammals contain all of the nutrients needed to
develop the offspring.
Q: The outer covering of a plant cell is called the __________.
(a) cell membrane
(b) cell wall
(c) cytoskeleton
(d) vacuole
A: (b)
Feedback: The cell wall surrounds the outside of a plant cell.
Q: Organisms whose cells have no visible nucleus are called eukaryotes. (True or False)
A: False
Feedback: Organisms whose cells have no visible nucleus are called prokaryotes.
Q: Name four cell organelles and their functions
A: May include the cell wall, cell membrane, cytoskeleton, ER, vacuole, chloroplasts, nucleus,
golgi apparatus, mitochondria, etc.
Feedback: The organelles inside the cell perform many important functions which sustain the
cell.
Q: Name two types of proteins, and describe what each one does.
A: May include chlorophyll, hemoglobin, enzymes, etc.
Feedback: Proteins make up most of the mass of an organism.
Q: Chromosomes are made up of ribosomes. (True or False)
A: False
Feedback: The chromosomes are made up of DNA which carry all the organism’s genetic information.
Q: The _______________ is the transportation system of the cell.
(a) mitochondria
(b) cytoskeleton
(c) endoplasmic reticulum (ER)
(d) cell membrane
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A: (c)
Feedback: The ER transports molecules around the cell.
Q: A tree trunk is so strong because its cells have very thick ______________.
(a) cell walls
(b) cell membranes
(c) nuclei
(d) vacuoles
A: (a)
Feedback: The cell wall provides the tree with strong support.
Q: Chromosomes are found in the nucleus of the cell. (True or False)
A: True
Feedback: The chromosomes are made up of DNA which carry all the organism’s genetic information.
Q: If the vacuoles of a tomato plant are not full of water, ________________.
(a) the tomatoes will not get red.
(b) the tomatoes will not grow.
(c) the plant will wilt.
(d) the plant will need more sun.
A: (c)
Feedback: The plant will wilt if the vacuoles are not full enough to provide adequate turgor to
support the plant.
ADDITIONAL RESOURCES
WEB SITES
Communication Technology Lab of Michigan State University “Microbe Zoo”
www.commtechlab.msu.edu
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
Life Science Connections—Life Science Safari
http://vilenski.org/science/safari
Cells alive!
www.cellsalive.com
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PUBLICATIONS
The Cartoon Guide to Genetics by Larry Gonick, Mark Wheelis (Contributor). Harper Perennial,
1991. ISBN: 0062730991
Exploring The Way Life Works: The Science of Biology by Mahlon B. Hoagland, Bert Dodson,
Judith Hauck. Jones & Bartlett Pub., 2001. ISBN: 076371688X
The Origin of Species by Charles Darwin. Grammercy, 1998. ISBN: 0517123207
Other End of the Microscope: The Bacteria Tell Their Own Story, by Bert Dodson (Illustrator),
Eleanor S. Tupper (Editor), Elmer W. Koneman. American Society for Microbiology, 2002.
ISBN: 1555812279
The Way Life Works by Mahlon Hoagland and Bert Dodson. Times Books, 1995.
ISBN:0812920201
OTHER PRODUCTS
Playing God: Human Cloning, VHS/DVD, Cambridge Educational
This program presents an in-depth exploration of the ethical concerns regarding human cloning.
A variety of perspectives are canvassed from the theological, legal, and scientific fields, including
interviews with Dr. Ian Wilmut, the first scientist to successfully clone a mammal—Dolly, a sheep.
Order #: 29332, www.cambridgeeducational.com, 1-800-468-4227
Cellular Respiration, VHS/DVD, Cambridge Educational
This six-part series begins by examining the essential fuels and machinery used by living forms to
sustain themselves. The fuel glucose is then broken down through the processes of glycolysis, the
Krebs cycle, and oxidative phosphorylation. Finally, the connections between the processes of cellular respiration and nutrition are examined. The series includes The Cell and Energy, Glycolysis 1,
Glycolysis 2, The Krebs Cycle, Oxidative Phosphorylation, Metabolism and Nutrition
Order #: 3668, www.cambridgeeducational.com, 1-800-468-4227
Sequencing Life, VHS/DVD, Cambridge Educational
In this program, Doctors Francis Collins, head of the Human Genome Project, and J. Craig
Venter, CEO of Celera Genomics, discuss the completion of the mapping of the human genome
and what that achievement means for the future of medicine. Initial discoveries indicate that the
structure of human DNA is simpler but its functions far more complex than previously imagined.
Order #: 29088, www.cambridgeeducational.com, 1-800-468-4227
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