Microscopic
Life
Teacher's Guide
Editors:
Brian A. Jerome, Ph.D.
Stephanie Zak Jerome
Assistant Editors:
Anneliese Brown
Louise Marrier
Graphics:
Lyndsey Canfield
Dean Ladago
Fred Thodal
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Table of Contents
Visual Learning Company 1-800-453-8481
A Message from our Company
2
Viewing Clearances
2
Use and Copyright
2
National Standards Correlations
4
Student Learning Objectives
5
Assessment
6
Introducing the Program
7
Program Viewing Suggestions
7
Video Script
8
Answer Key to Student Assessments
12
Answer Key to Student Activities
13
Pre-Test
14
Post-Test
16
Video Review
18
Vocabulary
19
Writing Activity
20
Models of Bacteria
21
Protist Overview
23
Microorganism Make-Believe
25
Microscopic Life
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National Standards Correlations
Benchmarks for Science Literacy
(Project 2061 - AAAS) Grades 3-5
The Living Environment - Cells (5C)
By the end of the 5th grade, students should know that:
• Some living things consist of a single cell. Like familiar organisms, they need
food, water, and air; a way to dispose of waste; and an environment they can live
in.
• Microscopes make it possible to see that living things are made mostly of
cells. Some organisms are made of a collection of similar cells that benefit from
cooperating. Some organisms’ cells vary greatly in appearance and perform very
different roles in the organism.
National Science Education Standards
(Content Standards: K-4, National Academy of Sciences)
Life Science - Content Standard C
As a result of their activities in grades 5-8, all students should develop an
understanding of:
Structure and Function in Living Systems
• All organisms are composed of cells - the fundamental unit of life. Most
organisms are single cells; other organisms, including humans, are multicellular.
Populations and Ecosystems
• Populations of organisms can be categorized by the function they serve in an
ecosystem. Plants and some microorganisms are producers - they make their own
food. All animals, including humans, are consumers, which obtain food by eating other
organisms. Decomposers, primarily bacteria and fungi, are consumers that use waste
materials and dead organisms for food. Food webs identify the relationships among
producers, consumers, and decomposers in an ecosystem.
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Student Learning Objectives
Upon viewing the video and completing the enclosed student activities, students
will be able to do the following:
• Understand that only during the past few hundred years have people been able
to see and study very small life forms, generally referred to as microscopic life.
• Explain how compound light microscopes magnify objects by passing light
through an object on a glass slide and then through two or more lenses.
• Understand there are other microscopes, such as electron microscopes, that
can magnify objects up to one million times their original size.
• Describe some of the general characteristics of viruses.
• List some of the ways viruses can affect human beings.
• Explain that viruses are single-celled organisms that do not have a nucleus.
• Cite some of the many positive contributions of bacteria, including their important
role in the decomposition of once-living things, production of certain types of
medicines, and production of various foods.
• Differentiate between protists and bacteria.
• Explain how protists can be plant-like, animal-like, or fungus-like. Provide an
example of a specific organism belonging to these groups.
• Describe the general characteristics of phytoplankton, a type of plant-like protist.
• Explain that animal-like protists, also called protozoa, are single-celled and come
in many forms.
• Briefly describe the general characteristics and some of the uses of fungus-like
protists.
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Assessment
Preliminary Test (p. 14-15):
The Preliminary Test is an assessment tool designed to gain an
understanding of students’ preexisting knowledge. It can also be used as a
benchmark upon which to assess student progress based on the objectives
stated on the previous pages.
Post-Test (p. 16-17):
The Post-Test can be utilized as an assessment tool following student
completion of the program and student activities. The results of the
Post-Test can be compared against the results of the Preliminary Test to
assess student progress.
Video Review (p. 18):
The Video Review can be used as an assessment tool or as a student
activity. There are two sections. The first part contains questions displayed
during the program. The second part consists of a five-question video quiz
to be answered at the end of the video.
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Introducing the Program
Before showing the video program to students, ask them if they have had a
cold or infected cut recently. Next, ask them if they have any idea what caused
these problems. Explain to students that most colds, as well as the flu, are
caused by tiny particles called viruses. Write the term “virus” on the board.
Next, explain that most infected cuts are caused by harmful bacteria living
in the cut. If an infection gets severe, a serious medical condition can arise.
Write the term “bacteria” on the board. Explain that even though bacteria can
be harmful, most are not. In fact, bacteria serve many useful purposes. Tell
students to pay close attention to the video to learn more about viruses and
bacteria.
Explain to students that the video program also discusses another group of
organisms called protists. Write the term “protist” on the board. Hold up the
following in front of the class: a package of yeast, a piece of algae or picture of
phytoplankton, and a picture of a protozoa. Tell students that these organisms
are all protists, but they are very different from each other. Ask students to pay
close attention to the video to learn about the different categories of protists.
After showing the video to students, have them categorize the examples into
protist groups.
Program Viewing Suggestions
The student master “Video Review” (p. 18) is provided for distribution to
students. You may choose to have your students complete this master while
viewing the program or do so upon its conclusion.
The program is approximately 14 minutes in length and includes a five-question
video quiz. Answers are not provided to the Video Quiz in the video, but are
included in this guide on page 12. You may choose to grade student quizzes
as an assessment tool or to review the answers in class.
The video is content-rich with numerous vocabulary words. For this reason you
may want to periodically stop the video to review and discuss new terminology
and concepts.
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Video Script
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A drop of pond water,...
...a tiny amount of soil,...
...and a single drop of blood all contain thousands of tiny living things.
These living things are so small they can’t be seen with the naked eye.
But scientists have developed special tools called microscopes to see these
fascinating organisms.
For this reason, these organisms are often referred to as microscopic living things,
or microscopic life.
Microscopic life is incredibly important to all living things, including us.
Just about everything we see, touch, and eat contains microscopic organisms.
During the next few minutes, we are going to take a brief look at some of the
different types of microscopic organisms,...
...while exploring some of their fascinating characteristics.
Graphic Transition – Seeing Microscopic Life
You Observe! Describe what you see in this drop of water.
It is hard to see anything but clear water.
It is certainly hard to imagine that this single drop of water...
...contains hundreds of amazing organisms so small they can only be seen with a
microscope.
Until the past few hundred years, people knew very little about the microscopic
world.
In 1590, a man who made reading glasses put two lenses together to create the
first compound microscope.
Today, compound light microscopes are widely used. There may even be one in
your classroom.
With a compound light microscope, light passes through an object on a glass slide
and then through two or more lenses.
Common compound light microscopes can magnify objects from 430 up to 1000
times their original size.
Objects too small to be seen with a compound light microscope are viewed with
other microscopes, such as electron microscopes,...
...which can magnify images up to one million times their original size!
This electron microscope, called a scanning electron microscope,...
...is used to study the outside of objects, such as the outer membrane of a cell.
Graphic Transition – What is a Virus?
You’ve probably heard people talk about viruses that infect computers.
This phrase is borrowed from the way real viruses infect living things.
So, what exactly is a virus?
Viruses are tiny particles that are considered neither dead nor living.
Viruses use living cells to reproduce before bursting outside the cell to invade
other cells.
Microscopic Life
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Video Script
31. Viruses are incredibly tiny. In fact, as many as 5 billion can fit in a single drop of
blood.
32. Because viruses are so small, they have been difficult to study.
33. If you have ever had a cold, most likely it was caused by a virus.
34. There are many viruses that can affect human beings.
35. Some viruses, such as measles, influenza, small pox, and HIV, can cause death to
large numbers of people.
36. Fortunately, scientists have developed vaccines to protect us from many, but not all,
dangerous viruses.
37. Graphic Transition – Bacteria
38. The smallest and most numerous living things on Earth cover your skin,...
39. ...inhabit the soil in which vegetables grow,
40. ...and even thrive in these boiling geothermal springs.
41. These microscopic living things, which are found almost everywhere, are called
bacteria.
42. Bacteria are small, single-celled organisms. Also referred to as monerans, bacteria
are the simplest living things...
43. ...and are believed to be the most ancient life forms on the planet.
44. Bacterial cells are different from other types of cells in that they do not have a
nucleus.
45. There are thousands of different kinds of bacteria, with new ones still being
discovered.
46. You Decide! Is there bacteria in food?
47. Yes, some types of bacteria are used in making foods, such as this yogurt.
48. In some cases, however, bacteria can be harmful.
49. If you have ever had an infected cut, bacteria probably caused the infection.
50. Bacteria can also cause sicknesses, such as strep throat, tuberculosis, and bacterial
pneumonia.
51. Bacteria are incredibly important to life on Earth.
52. For example, bacteria play a very important role in decomposing once-living things
and recycling important nutrients so they can be used by other organisms.
53. Bacteria are also useful in creating certain types of medicines.
54. Bacteria are essential to the survival of humans in many ways.
55. For example, they are found in abundance in the body, and even help us digest food.
56. Graphic Transition – Protists
57. It’s hard to believe that this amoeba, this phytoplankton, and these yeast cells all
have something in common. What is it?
58. They are all members of a large group of organisms called protists.
59. One of the big differences between protists and bacteria is that protists have a
nucleus.
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Video Script
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Most protists are microscopic and are made up of one cell.
But some, such as different types of algae, are made up of many cells.
Many protists, such as this amoeba, need to eat other things for energy.
But some protists, like this algae on the seacoast, produce their own food from the
sun’s energy.
Other types of protists, like this slime mold, live off dead plants or animals.
Protists can be plant-like, animal-like, or fungus-like.
Let’s take a quick look at plant-like protists.
Every time you go swimming in the ocean, you are surrounded by millions of tiny
microscopic plant-like organisms generally referred to as phytoplankton.
Phytoplankton are microscopic plant-like protists that float in water.
They provide food for many different types of animals.
They also give off tremendous amounts of oxygen, which all animals, including
humans, need to survive.
There are many different groups of plant-like protists...
...with a wide range of shapes, sizes, and forms.
Some are even used in making toothpaste, paint, and foods.
You Compare! How is an amoeba different from a plant-like protist?
Unlike many plant-like protists, animal-like protists, such as amoebas and
paramecium, move.
They also need to eat other living things or once-living things for food.
Animal-like protists, also called protozoa, are single-celled and come in many
different forms.
The amoeba, for example, has a body shape that continually changes.
Amoeba feed by engulfing food.
Other protozoa, such as paramecium, have hundreds of hair-like structures that
move back and forth, propelling the paramecium through the water.
In 1845 and 1846, Ireland’s Great Potato Famine was responsible for the deaths of
1/3 of Ireland’s people and caused hundreds of thousands more to flee the country.
A fungus-like protist called water mold is blamed for destroying the potato crop.
Fungus-like protists obtain their energy by consuming living or once-living things.
There is a wide range of fungus-like protists, and while some are destructive, many
are quite useful.
Yeast is a fungus-like protist used to make bread. Other fungus-like protists are used
to produce cheeses, antibiotics, and even soy sauce.
Graphic Transition – Summing Up
During the past few minutes, we have discussed the fascinating world of
microscopic life.
We began by discussing viruses, which are tiny particles, that are neither living nor
dead.
10
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Video Script
89. We learned that bacterial cells are smaller than other cells and do not have a
nucleus.
90. We then explored some of the roles bacteria play on Earth, such as decomposing
once-living organisms, making certain types of medicine and foods, and causing
some sicknesses.
91. We learned that protists are made up of one or more cells and have a nucleus.
92. We compared the structure and role of plant-like, animal-like, and fungus-like
protists.
93. More specifically, we learned that plant-like protists, also called algae, can make
food from sunlight,…
94. …whereas animal-like protists, also called protozoa, and fungus-like protists need
to eat living or once-living things.
95. So, the next time you eat a cup of yogurt,…
96. …drink a glass of water,…
97. …or take medicine,…
98. …think about some of the things we discussed during the past few minutes.
99. You just might think about microscopic life a little differently.
100. Graphic Transition – Video Assessment
101. Fill in the correct word to complete the sentence. Good luck and let’s get started.
1. ______ are particles that are neither living nor dead.
2. Bacteria are ______ than other cells.
3. Protists possess a cell with a ______.
4. _______ protists make their own food from the sun’s energy.
5. Animal-like protists are also called ______.
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Answer Key to Student Assessments
Pre-Test (p. 14-15)
Post-Test (p. 16-17)
1. c - microscopes
2. d - a virus
3. a - smaller
4. c - monerans
5. a - decomposition
6. d - nucleus
7. a - plant-like
8. a - amoebas and paramecium
9. b - protozoa
10. d - living or once-living things
11. true
12. true
13. false
14. false
15. false
16. Microscopes enlarge objects too small
to be seen with the naked eye.
17. Monerans are microscopic organisms,
also called bacteria.
18. Viruses are much smaller than animal
cells.
19. Phytoplankton consist of plant-like
protists that live in water.
20. Examples of animal-like protists
include amoebas and parameciums.
1. a - smaller
2. d - nucleus
3. b - protozoa
4. d - a virus
5. a - plant-like
6. c - microscopes
7. a - amoebas and paramecium
8. a - decomposition
9. d - living or once-living things
10. c - monerans
11. false
12. false
13. false
14. true
15. true
16. Phytoplankton consist of plant-like
protists that live in water.
17. Viruses are much smaller than animal
cells.
18. Examples of animal-like protists
include amoebas and parameciums.
19. Monerans are microscopic organisms,
also called bacteria.
20. Microscopes enlarge objects too small
to be seen with the naked eye.
Video Review (p. 18)
1. It is hard to see anything other than clear water.
2. Yes, some types of bacteria are used in making foods, such as yogurt.
3. Unlike many plant-like protists, animal-like protists, such as amoebas, move and need
to eat other living things or once-living things.
1.
2.
3.
4.
5.
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Viruses are particles that are neither living nor dead.
Bacteria are smaller than other cells.
Protists possess a cell with a nucleus.
Plant-like protists make their own food from the sun’s energy.
Animal-like protists are also called protozoa.
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Answer Key to Student Activities
Vocabulary (p. 19 )
Models of Bacteria (p. 21-22)
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
(A)1. Cocci are spherical-shaped bacteria.
2. Cocci can exist as single cells,
in pairs, in chains, and in clusters.
3. Streptococcus bacteria cause strep throat.
Meningitis is caused by Neisseria
meningitidis.
(B)1. Bacilli are rod-shaped bacteria.
2. Bacilli most often appear as single cells,
but may form chains.
3. Tetanus, anthrax, diphtheria, and botulism
are caused by bacilli bacteria.
(C)1. Spirilla are spiral- or coil-shaped bacteria.
2. Spirilla only exist as a single cell.
3. Cholera is caused by a spirrila bacteria.
microscope
viruses
bacteria
decomposition
protists
plant-like protists
phytoplankton
animal-like protists
protozoa
yeast
Writing Activity (p. 20)
Scientists have developed special tools
called microscopes that enable us to
see things too small to be seen with the
naked eye. Viruses are among the tiniest
microscopic particles. Bacteria, also
called monerans, are the simplest living
things. These cells do not possess a
nucleus. Bacteria play a very important
role in decomposing once-living things and
recycling nutrients. Protists are organisms
that have a nucleus. Most, but not all, are
microscopic. Plant-like protists produce
their own food from the sun’s light energy.
Animal-like protists, also called protozoa,
must eat living things or once-living things
for food. Yeast, a fungus-like protist, is
used to make bread.
In Your Own Words (p. 20)
1. Microscopes help us see and study
organisms, such as bacteria and protists,
that cannot be seen with the naked eye.
2. Bacteria play a vital role in
decomposing once-living things and
recycling nutrients so they are useful to
living things. Bacterias are also useful in
making certain foods and medicines.
3. Phytoplankton are plant-like protists
that float in water.
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Protist Overview (p. 23-24)
(1) a. Plant-like protist.
b. Can be single-celled or multicellular.
Produce food via photosynthesis. Can
have many forms.
c. Live in water.
d. Produce own food from sun’s light energy.
(2) a. Animal-like protist.
b. Tend to be single-celled. Great diversity in
shape and structure.
c. Live in water or other moist environments.
d. Need to eat living things or once-living
things for energy.
(3) a. Fungus-like protist.
b. Three main groups; often called molds.
Can grow on things and even live in water.
c. Tend to live in damp or watery places.
d. Most often eat dead organic matter.
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Pre-Test
Name
Circle the best answer for each of the following questions.
1. Microscopic organisms are commonly viewed with instruments called:
a. tweezers
b. magnifiers
c. microscopes
d. telescopes
c. sneezing
d. a virus
c. more interesting
d. faster
2. Most colds are caused by:
a. bad water
b. cold temperatures
3. Compared to a blood cell, viruses are:
a. smaller
b. larger
4. Bacteria are small, single-celled organisms also referred to as:
a. plants
b. fungi
c. monerans
d. vertebrates
c. movement
d. succession
5. This process could not occur without bacteria:
a. decomposition b. mitosis
6. One of the differences between protists and bacteria is that protists have a:
a. brain
b. mouth
c. heart
d. nucleus
7. Phytoplankton fall into the following protist group:
a. plant-like
b. animal-like
c. fungus-like
d. mammal-like
c. algae
d. slime mold
c. diatoms
d. algae
8. Examples of animal-like protists include:
a. amoebas and
paramecium
b. plants
9. Animal-like protists are also referred to as:
a. dinoflagellates b. protozoa
10. Fungus-like protists obtain their energy by consuming:
a. sun’s energy
b. water
c. viruses
d. living or
once-living
things
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Pre-Test
Name
Write true or false next to each statement.
11.
Viruses reproduce inside living cells.
12.
Bacteria are found almost everywhere, even inside the human
body.
13.
Bacteria have no useful purpose.
14.
All protists look the same.
15.
Phytoplankton are examples of animal-like protists.
Write a short answer for each of the following.
16. What is the purpose of microscopes?
17. What are monerans?
18. How does the size of viruses compare to animal cells?
19. What is phytoplankton?
20. List two examples of animal-like protists.
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Post-Test
Name
Circle the best answer for each of the following questions.
1. Compared to a blood cell, viruses are:
a. smaller
b. larger
c. more interesting
d. faster
2. One of the differences between protists and bacteria is that protists have a:
a. brain
b. mouth
c. heart
d. nucleus
c. diatoms
d. algae
c. sneezing
d. a virus
3. Animal-like protists are also referred to as:
a. dinoflagellates b. protozoa
4. Most colds are caused by:
a. bad water
b. cold temperatures
5. Phytoplankton fall into the following protist group:
a. plant-like
b. animal-like
c. fungus-like
d. mammal-like
6. Microscopic organisms are commonly viewed with instruments called:
a. tweezers
b. magnifiers
c. microscopes
d. telescopes
c. algae
d. slime mold
c. movement
d. succession
7. Examples of animal-like protists include:
a. amoebas and
paramecium
b. plants
8. This process could not occur without bacteria:
a. decomposition b. mitosis
9. Fungus-like protists obtain their energy by consuming:
a. sun’s energy
b. water
c. viruses
10. Bacteria are small, single-celled organisms also referred to as:
a. plants
b. fungi
c. monerans
d. living or
once-living
things
d. vertebrates
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Post-Test
Name
Write true or false next to each statement.
11.
All protists look the same.
12.
Bacteria have no useful purpose.
13.
Phytoplankton are examples of animal-like protists.
14.
Bacteria are found almost everywhere, even inside the human
body.
15.
Viruses reproduce inside living cells.
Write a short answer for each of the following.
16. What is phytoplankton?
17. How does the size of viruses compare to animal cells?
18. List two examples of animal-like protists.
19. What are monerans?
20. What is the purpose of microscopes?
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Video Review
Name
While you watch the video, answer these questions:
You Observe!
1. Describe what you see in this drop of water.
You Decide!
2. Is there bacteria in food?
You Compare!
3. How is an amoeba different from a plant-like protist?
After you watch the video, test your knowledge with these questions.
1. ______________ are particles that are neither living nor dead.
2. Bacteria are ______________ than other cells.
3. Protists possess a cell with a _____________.
4. ______________ protists make their own food from the sun’s energy.
5. Animal-like protists are also called ______________.
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Vocabulary
Name
Use these words to fill in the blanks next to the sentences below.
Words
bacteria
plant-like protists
microscope
protozoa
animal-like protists
protists
viruses
yeast
phytoplankton
decomposition
1.
An instrument used to enlarge objects too small to be seen with
the naked eye.
2.
Tiny particles considered neither living nor dead.
3.
Single-celled organisms also referred to as monerans.
4.
The process by which bacteria decay or break down once-living
things.
5.
Large group of organisms possessing a nucleus; many are
microscopic, but some are not.
6.
Organisms capable of creating their own food from sun’s light
energy.
7.
Microscopic plant-like protists that float in water.
8.
Single-celled organisms that must eat other living things or
once-living things for food.
9.
A term used to describe animal-like protists.
10.
An example of a fungus-like protist used in making bread.
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Writing Activity
Words
monerans
plant-like protists
fungus-like protist
protozoa
Name
viruses
microscopes
protists
decomposing
microscopic
nucleus
Use the correct word from above to complete the sentences in the following
paragraph.
Scientists have developed special tools called ________________________ that enable us to
see things too small to be seen with the naked eye. ________________ are among the tiniest
microscopic particles. Bacteria, also called ___________________, are the simplest living
things. These cells do not possess a _______________. Bacteria play a very important role in
_____________________ once-living things and recycling nutrients. ______________ are
organisms that have a nucleus. Most, but not all, are _______________.
_______________________ produce their own food from the sun’s light energy. Animal-like
protists, also called ______________, must eat living things or once-living things for food.
Yeast, a ______________________, is used to make bread.
In Your Own Words
1. Why are microscopes useful?
2. How are bacteria useful?
3. What are phytoplankton?
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Models of
Bacteria
Name
Background: Bacteria are probably the most numerous living things on the planet. Scientists
believe bacteria were the first living things on Earth. We can’t see bacteria with the naked
eye, but we know they exist just about everywhere. They are on furniture in your home, on
plants and animals, and even inside your body. Bacteria, also referred to as monerans, are
tiny, powerful organisms. They can make us sick with diseases such as strep throat and
bacterial penumonia. But, they are also very helpful. They provide us with healthy foods, such
as cheese and yogurt. Bacteria also break down, or decompose, once-living things, making
valuable nutrients available to other living things.
There is a wide range of bacterial types. In fact, there are hundreds of thousands of different
kinds of bacteria and more are still being discovered. Despite the wide variety of bacteria, most
bacteria have several common characteristics. Bacterial cells have cell membranes and cell
walls that surround the cell. They do not have a nucleus. Most bacteria do not make their own
food. Instead, they rely on other organisms for their energy. Bacterial cells are filled with a jellylike mixture called cytoplasm. Heredity material floats in the cytoplasm. The heredity material
contains the blueprint for the cell. These are some of the basic structures common to most
bacteria. Many bacteria also contain additional structures.
Bacteria are often classified based on their shape. There are three main shapes of bacteria.
Spiral-shaped bacteria are called spirilla. Round-shaped bacteria are called cocci. And,
rod-shaped bacteria are called bacilli. In this activity you will create a model of each bacterial
shape.
Materials:
frozen peas
rod-shaped candy
spiral-shaped pasta
biology textbooks, encyclopedia, and other resources on bacteria
Directions:
1. Work in groups of two or three people. Obtain the materials listed above.
2. Identify which item of food represents which of the three bacterial shapes: spirilla, cocci, or
bacilli.
3. Draw the bacterial model in the correct box on the following page.
4. Fill in the remaining information for each bacteria.
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Models of
Bacteria
Name
A. Cocci
1. Describe the shape of cocci bacteria.
2. Describe how these bacteria can be arranged.
3. Give an example of a disease caused by cocci
bacteria.
B. Bacilli
1. Describe the shape of bacilli bacteria.
2. Describe how these bacteria can be arranged.
3. Give an example of a disease caused by bacilli
bacteria.
C. Spirilla
1. Describe the shape of spirilla bacteria.
2. Describe how these bacteria can be arranged.
3. Give an example of a disease caused by spirilla
bacteria.
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Protist Overview
Name
Background: It’s hard to believe that amoebas, phytoplankton, and yeast cells all have
something in common. What is it? They are all members of a large group of organisms called
protists. One of the big differences between protists and bacteria is that protists have a nucleus.
Most protists are microscopic and are made up of one cell. But some, such as different types of
algae, are made up of many cells. Many protists, such as the amoeba, need to eat other things
for energy. But some protists produce their own food from the sun’s energy. Other types of
protists, like slime mold, live off dead plants or animals.
Protists can be plant-like, animal-like, or fungus-like. Let’s take a quick look at plant-like protists.
Every time you go swimming in the ocean, you are surrounded by millions of tiny microscopic
plant-like organisms called phytoplankton. Phytoplankton are microscopic plant-like protists
that float in water. They provide food for many different types of animals. They also give off
tremendous amounts of oxygen, which all animals, including humans, need to survive. There
are many different groups of plant-like protists with a wide range of shapes, sizes, and forms.
Some are even used in making toothpaste, paint, and foods.
Unlike plant-like protists, animal-like protists move. They also need to eat other living things or
once-living things for food. Animal-like protists, also called protozoa, are single-celled and come
in many different forms. The amoeba, for example, has a body shape that continually changes.
Amoeba feed by engulfing food. Other protozoa, such as paramecium, have hundreds of hairlike structures that move back and forth, propelling the paramecium through the water.
In 1845 and 1846, Ireland’s Great Potato Famine was responsible for the deaths of 1/3 of
Ireland’s people and caused hundreds of thousands more to leave the country. A fungus-like
protist called water mold is blamed for destroying the potato crop. Fungus-like protists obtain
their energy by consuming living or once-living things. There is a wide range of fungus-like
protists. Although some are destructive, many are quite useful. Yeast is a fungus-like protist
used to make bread. Other fungus-like protists are used to produce cheeses, antibiotics, and
even soy sauce.
Materials: life science or biology textbooks; encyclopedia; and other resource materials on
protists
Directions:
1. Research the three protists on the following page. Each organism represents a plant-like,
animal-like, or fungus-like protist.
2. Answer the following questions for each organism:
a. Is the organism a plant-like, animal-like, or fungus-like protist?
b. What are the general characteristics of this group of protists?
c. In what type of environment does it live?
d. How does it obtain food?
3. Draw another example in each protist group. For example, you could draw a paramecium as
an example of an animal-like protist.
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Protist Overview
Name
1.
Spirogyra
a.
b.
c.
d.
2.
Amoeba
a.
b.
c.
d.
3.
Slime Mold
a.
b.
c.
d.
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Microorganism
Make-Believe
Name
Background: Scientists have probably learned more about the microscopic
world in the past several decades than in any other branch of science.
And the more we learn, the more we realize how much is yet to be
learned about microorganisms. For example, a great deal of scientific
investigation has been conducted on harmful microorganisms responsible
for carrying diseases. Diseases caused by viruses such as HIV and
polio have been extensively studied. A lot of time has also been spent
studying microorganisms that help us to live better lives. For example,
microorganisms have been discovered that are used to digest sewage and
toxic waste. Scientists have also experimented with microorganisms helpful
in creating many different kinds of foods and medicines. New organisms are
still being discovered, as are new and beneficial uses of microorganisms. Who knows
what new and useful microorganisms will be discovered next!
Activity: The purpose of this fun activity is to create your own make-believe microorganisms.
Your microscopic creation may be harmful or helpful. Try to think in detail of what the
characteristics of your microorganism might be, how it lives, where it lives, how it moves from
one place to another, and the effect it has on other living things.
To help you get started, do this activity as a class. Each person in the class will contribute
to the creation of a microorganism. The first person will start off with a statement about the
microorganism. Here are some ideas:
This microorganism was born on my cereal....
or
This microorganism multiplied quickly....
or
A virus was found on a glass of milk.
Go around the room and have each person add a piece of information about the microorganism.
See how your class microorganism ends up after the last person contributes!
Now you will have an opportunity to write your own microorganism story.
Directions: Write about your microorganism on the back of this page. Make sure you describe
the environment in which it lives. Draw a picture of your microorganism on a separate piece of
paper. To help you get started, think about the following questions:
1.
2.
3.
4.
5.
Where does your microorganism live?
What type of microorganism is it?
Does it have a nucleus?
Is your microorganism helpful or harmful?
How is it helpful or harmful?
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