Name _____________________________________________________________
Microorganisms
Workbook I
When this workbook is complete, students are expected to
understand the following concepts:
STANDARD V: Students will understand that
microorganisms range from simple to complex, are found
almost everywhere, and are both helpful and harmful.
Standard/
Description
Objective
7.18.2
Use precise scientific language in oral and
written communication.
5.10.1
Examine and illustrate size, shape, and
structure of organisms found in an
environment.
On Your Mark, Get Set, Go!
Put away your running shoes and starting blocks. We’re not having a track meet;
we’re going to study microorganisms. Are you ready? Do you have any idea what you will
be learning? It’s always nice to have some idea where you are headed before you start
out on an adventure, so let’s see if we can get some kind of an idea. To do that, we will
look carefully at the word microorganism
Do you know what micro means? Have you ever used a microscope in your science
class or at home? Why did you use one? What kinds of things did you look at through
the microscope? Were they big or tiny? Did the microscope make them seem larger or
smaller? As you might have figured out, micro means small. That helps us some because
now we know we will be learning about something small.
The other part of our word is organism. According to the dictionary, an organism
is any form of life; any living thing. That helps us even more. Now we know we will be
learning about small, living things.
Wait a minute; we have to be sure we understand exactly what we mean when we
say we will learn about small living things. How small is small? Now we all know that an
elephant is pretty big! Does that mean that a mouse is small? Many bugs are even
smaller than mice! Are there other living things that are even smaller than bugs?
Let’s change our definition of micro just a bit. Let’s say that micro means too
small for the human eye to see. That gives us a better idea of the size of the living
things we will be studying.
Now, let’s be sure we really understand what we mean by living things. Scientists
have studied many living things. They have found that all living things are the same in
some ways. They all have some of the same characteristics. Let’s look at six
characteristics of all living things.
1. Living things are made of cells.
A cell is the basic unit of all living things. A cell is organized to help keep an
organism alive. A cell is responsible for reproduction, for growth and development, and
for responding to the environment. Some scientists say cells are like chemical
factories. They are always busy making something to keep their organisms alive and
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well. Some organisms have only one cell. Other organisms have many cells that work
together. All organisms are made of cells.
2. Living things use energy
Organisms get the energy they need from the environment. Energy is needed for
life processes. Organisms use energy to reproduce. They use energy when they grow
and develop. They also use energy when they respond to their environments. Organisms
must have a balance between the energy they get from the environment and the energy
they use for life processes. All organisms use energy.
3. Living things grow and develop.
Think about a tiny tadpole. The tadpole will get bigger, grow legs,
lose its tail, and become a frog or toad. The tadpole will grow and
develop to become an adult amphibian. Now think about a tiny
acorn. The acorn will fall to the ground, germinate, and form
roots, a stem, and leaves. The tiny acorn will grow and develop to become a
mighty oak tree. All organisms grow and develop.
4. Living things respond to the environment.
What happens if you touch a hot burner on the stove in your kitchen? You pull
your finger away very quickly! You respond to the environment. When you touch the hot
burner, you have a stimulus. A stimulus is a change in the environment. When you pull
your finger away very quickly, you have a response. A response is the reaction to the
change in the environment. All organisms respond to the environment.
5. Living things reproduce.
When organisms reproduce, they make more organisms that look like themselves.
If your dog has puppies, the puppies look like the parent dogs. If a dandelion goes to
seed in your yard, you will have more dandelions that look just like the first one! All
organisms reproduce.
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6. Living things are adapted to their environments.
Think about a Downy Woodpecker. It has four toes on each foot.
Two of the toes are facing forward, and two of them are facing backward.
The woodpecker’s toes help it hold onto the bark of a tree. It also has a
stiff tail. This tail helps the woodpecker balance against the trunk of a
tree as it drills a hole in the bark.
A Downy Woodpecker also has a thick, pointed bill. The bill allows the
woodpecker to make holes in the hard wood of a tree to find insects. Finally, it has a
long tongue. The woodpecker can put its tongue into the tree to find insects. There is a
tiny barb on the end of the tongue that can hook the insects and carry them back in to
the woodpecker’s mouth for a tasty lunch or dinner. An organism must be adapted to
the environment to be able to survive. All organisms have adaptations that allow them
to live in their environments.
All living things have all six characteristics. Some kinds of matter may have one
or two characteristics, but not all six. If it does not have all six characteristics, it is
not an organism. Every organism must have all six characteristics.
Okay, let’s review our definition. A microorganism is a tiny living thing that is too
small for the human eye to see. It is made of cells, uses energy, grows, and develops,
responds to it environment, reproduces, and is adapted to survive in its environment.
What Do You Need?
All living things have six characteristics in common. We just learned what those
six characteristics are. They also have basic needs that are the same. Let’s take a
look at what those basic needs are.
Energy
All organisms need energy. The Sun is the main source of energy for most life on
Earth. All living things either use the Sun directly or indirectly. Producers are
organisms that make their own food by using the Sun’s energy. They use their
“homemade” food to provide their energy. Without direct energy from the Sun,
producers would not be able to survive.
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Consumers are organisms that eat other organisms. Some consumers eat plants.
Plants are producers. The plants use the Sun’s energy directly, but consumers still
depend on the Sun’s energy in an indirect way. Without energy from the Sun for the
producers, consumers would not have the food they need for energy.
Food
Imagine a day without food. You would feel pretty lousy if you could not eat
anything all day. Your body needs food for proper growth. As we have already learned,
producers are organisms that make their own food. They absorb nutrients from the
environment and use those nutrients to help keep them alive.
Remember that consumers are organisms that eat other organisms. There are
three basic groups of consumers. Herbivores are consumers that eat only plants.
Carnivores are consumers that eat only animals. Omnivores are consumers that eat
both plants and animals. All consumers get nutrients from their food sources.
Water
Organisms need water to stay alive. Water is used to dissolve and transport
substances. Nutrients are dissolved and wastes are transported in an organism’s water
supply.
Humans need water more than they need food. You can survive for a week or
more without food; however, you can only survive for a matter of days without water.
More than 70% of the human body is actually water. Water is needed by almost all of
your body systems.
For most organisms, not just any water will do. Most organisms require fresh
water; however, the majority of the Earth’s water is found in the oceans, which are salt
water. Most organisms cannot survive using salty ocean water. For example, ocean
water has more than seven times the amount of salt that a human body can handle. In
order to use ocean water, the salts must be removed.
Microorganisms Questions
1. What does the word micro mean?
__________________________________________________________________
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2. Using the meaning of the word micro, develop a definition for each of the following
terms:
a. microclimate – _______________________________________________
b. microfilm – _________________________________________________
c. micrometer – ________________________________________________
d. microsurgery – _______________________________________________
3. What does the word organism mean?
__________________________________________________________________
4. What are the six characteristics of all living things?
a. ___________________________________________________________
b. ___________________________________________________________
c. ___________________________________________________________
d. ___________________________________________________________
e. ___________________________________________________________
f. ___________________________________________________________
5. What is a microorganism?
__________________________________________________________________
6. What is a producer?
__________________________________________________________________
7. What is a consumer?
__________________________________________________________________
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8. How is a consumer different from a producer?
__________________________________________________________________
__________________________________________________________________
It’s So Simple: Kingdom Monera (Bacteria)
Scientists put all living things into five kingdoms: Monera, Protista, Fungi,
Plantae, and Animalia. (We’ll look at Monera, Protista, and Fungi). Let’s look at
Monerans.
Cell Structure
Moneran cells to not have a nucleus (brain). They are called prokaryotes, which
means “before a nucleus.” They also don’t have any organelles (“little organs”) to help
with life processes. They do have cell membranes and some of the also have cell walls.
Some kinds of Monerans have chlorophyll, as well (this makes them producers).
Number of Cells
Monerans are the simplest kinds of organisms. They have only one cell (singlecelled organism).
Kinds of Movement
Some kinds of Monerans are able to move on their own. They use simple
structures that look like whips. These are called flagella. Others cannot move.
Nutrition
Some Monerans are producers. Others are consumers.
Is it Moneran or Not?
Any organism that has these specific characteristics is a Moneran. If it doesn’t
have these characteristics, it’s not a Moneran.
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1. I have recently found a new organism. I need to classify it. I think it should be
classified as a Moneran. Look at the following characteristics and see if you agree with
me. (Circle your answer).
a. My new organisms are very tiny. When I see it in the microscope, I notice it is
only one cell.
Could this be a Moneran?
Yes
No
b. When I look closely inside the cell, I notice there is no nucleus. I don’t notice
any organelles inside the cell.
Could this be a Moneran?
Yes
No
c. This cell does not seem to be able to move. I do not notice any structures on
or in the cell that would help it move.
Could this be a Moneran?
Yes
No
d. This cell has a cell wall and chlorophyll. It is able to use the Sun’s energy to
make its own food. It does not have any cell structures that would allow it to use other
organisms for food.
Could this be a Moneran?
Yes
Is this organism a Moneran?
No
Yes
No
It’s Still Pretty Simple: Kingdom Protista (Protozoan)
Cell Structure
Protozoans do have a nucleus and it’s
surrounded by a nuclear membrane. They are
called eukaryotes, which means “true nucleus.”
They also have cell organelles that help the nucleus
perform all the life processes.
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Number of Cells
cells.
Most Protozoans are single-celled organisms. A few are made up of two or more
Kinds of Movement
Some Protozoans do not move at all, but many of them are able to move. Some
protists use psuedpods, or false feet. The cell in this type of protists is able to change
its shape. It is able to extend some of the cytoplasm to make a fake foot or two. The
feet are able to push or pull the cell along.
Other protists move using tiny, hair-like structures called cilia. The cilia are
found on the outside of the cell. They are able to move very quickly back and forth,
moving the protists along through water or another liquid.
Finally, some protists move using flagella. These are simple, whip-like structures
that propel the protist through its environment.
Nutrition
Some protists are producers and have chloroplasts and chlorophyll. Others are
consumers.
Is it a Protist or Not?
Any organism that has these specific characteristics is a Protista. If it doesn’t
have these characteristics, it’s not a Protista.
1. Guess what? I have found some new organisms. I think they should be classified as
either Moneran or Protist, but I’m not sure. Look at the following characteristics and
see if you can decide which kingdom they should be in.
a. When I look at one of the organisms in the microscope, I notice a tiny nucleus
inside the cell. A membrane surrounds the nucleus.
This organism should be classified as a Moneran Protist
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b. When I look at the next organism, I notice it has more than one cell. I don’t
see any tissues or organs, but the group of cells seems to be one organism, not a colony.
This organism should be classified as a Moneran Protist
c. This organism is moving. I notice that it is a single cell, with a flagellum. I
cannot tell if this organism has a nucleus or not.
This organism should be classified as a Moneran Protist Could be either
d. This is a simple organism with chloroplasts in its cell. It makes its own food.
This organism should be classified as a Moneran Protist
This organism is most likely a: Moneran Protist
The Amoeba
(modified from The Biology Corner – Worksheets and Lessons)
The amoeba is a protozoan. It belongs to Kingdom Protista. Protists are microscopic
one-celled organism. The amoeba is an animal-like protist. It can move and consumes its
food (consumer). The amoeba moves by stretching its cytoplasm. These are called
pseudopods ("false foot"). The amoeba can change its shape. Amoeba live in ponds or
puddles, and can even live inside people.
The pseudopods help an amoeba to eat. They surround the food and put it in a food
vacuole. The food is digested while in the food vacuole.
Amoebas can cause disease. One disease caused by the amoeba is called Amoebic
Dysentery. A person becomes infected by drinking unsanitary water. The amoeba upsets
the person's digestive system and causes cramps and diarrhea.
Questions
1. How does an amoeba move?
__________________________________________________________________
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2. What disease is caused by the amoeba?
__________________________________________________________________
3. To what Kingdom does the amoeba belong?
__________________________________________________________________

Cytoplasm
 The long finger-like extensions are the pseudopods. When you color them, color only
the finger-like extension. The interior of the amoeba is the cytoplasm.
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The Euglena
(modified from The Biology Corner – Worksheets and Lessons)
Euglena are one-celled organisms. They belong to Kingdom Protista. All Euglena have
chloroplasts. Chloroplast allow Euglena to make their own food (they are producers). Euglena
can also absorb food from their environment. Euglena live in ponds or puddles.
Euglena move by a flagellum (plural ‚ flagella), which is a long whip-like structure that acts like a
little motor. The flagellum is located on the front end, and twirls in such a way as to pull the
cell through the water. Color the reservoir light blue and the flagellum black.
Chloroplasts use sunlight to make the Euglena’s food. They are rod-like structures throughout
the cell. Color the chloroplasts green. Euglena have an eyespot at the front end. It detects
light. This helps the Euglena find bright areas to gather sunlight to make their food. Color the
eyespot red.
The Euglena has a stiff pellicle outside the cell membrane. It helps it keep its shape. The
Euglena can also move like an inchworm. Color the pellicle blue.
In the center of the cell is the nucleus. It controls the cell’s activities. The nucleolus can be
seen within the nucleus. Color the nucleus purple, and the nucleolus brown.
The interior of the cell contains a jelly-like fluid called cytoplasm. Color the cytoplasm yellow.
Toward the back of the cell is a star-like structure. This is the contractile vacuole. It helps
remove excess water. If it got too much water, the cell would explode. Color the contractile
Pvacuole orange.
A man goes to the eye doctor. The receptionist asks him why he is
there. The man complains, "I keep seeing spots in front of my
eyes."
The receptionist asks, "Have you ever seen a doctor?" and the
man replies, "No, just spots."
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Color the Euglena according to
the directions. Organelles can
be identified based on their
descriptions and locations.
Answer the following questions
1. Are euglena unicellular or
multicellular?
_____________________
2. What Kingdom do euglena
belong to?
_____________________
3. What organelle carries
out photosynthesis?
_____________________
4. On which end is the
flagellum located?
_____________________
5. What is the eyespot used
for?
_____________________
_____________________
6. What is the function of
the nucleus?
_____________________
_____________________
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7. What is the function of the contractile vacuole? What would happen if the cell did
not have this organelle?
__________________________________________________________________
__________________________________________________________________
The Paramecium
(modified from The Biology Corner – Worksheets and Lessons)
Paramecium are protozoans. They belong to Kingdom Protista. They live in quiet or
stagnant ponds. They eat algal scum and other microorganisms. Small organisms eat
them. They move by tiny hair-like projections called cilia. Color all cilia black.
The paramecium cannot change its shape. This is because it has a thick outer membrane
called the pellicle. Color the pellicle light blue.
There are two types of nuclei (plural of nucleus). The large nucleus is called the
macronucleus, It controls respiration, protein synthesis and digestion. Color the
macronucleus red. The much smaller micronucleus is used only during reproduction, color
the micronucleus yellow.
Contractile vacuoles are used in animal cells to remove the excess water. The
contractile vacuole is shaped like a star - color the contractile vacuole dark green.
Paramecium are consumers. Food enters the paramecium through the mouth pore (color
orange) and goes to the gullet (color dark blue). At the end of the gullet, food vacuoles
are formed. Food vacuoles remain in the cytoplasm until the food is digested. Color all
food vacuoles light brown. Undigested food particles are eliminated through the anal
pore (color dark brown). The indented area where food enters the paramecium is
referred to as the oral groove.
Just inside the pellicle are trichocysts. The paramecium can shoot tiny threads out of
the cell to entangle a predator or to make themselves appear bigger. Color the
trichocysts purple
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Paramecium Questions:
1. Is the paramecium a unicellular or multicellular organism?
__________________________________________________________________
2. What do paramecium eat?
__________________________________________________________________
3. What is the function of the contractile
vacuole?
___________________________________
___________________________________
4. Where do paramecium live?
___________________________________
___________________________________
Key to Diagram
1. Cilia
2. Pellicle
3. Macronucleus
4. MicroNucleus
5. Contractile
Vacuole
6. Mouth Pore
7. Gullet
8. Food Vacuole
9. Anal Pore
10. Trichocysts
11. Ectoplasm
12. Endoplasm
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For the Last Time, It’s Simple: Kingdom Fungi (Fungus)
Cell Structure
Fungi cells have a nucleus that is surrounded by a nuclear membrane. Like
protists, they are called eukaryotes. Fungi have cell organelles that help the nucleus
perform all life processes.
Number of Cells
Some fungi are single-celled organisms. Many of the members of this kingdom
are many celled.
Kinds of Movement
Fungi can’t move on their own.
Nutrition
Fungi do not have any chlorophyll. They are unable to make their own food;
therefore, they are not considered producers. They are not able to actually eat other
organisms, either. Instead, fungi are able to absorb nutrients from any other
organisms. Most fungi get their nutrition from dead or dying matter, so they are
classified as saprophytes.
Is it Fungi or Not?
Any organism that has these specific characteristics is a Fungus. If it doesn’t
have these characteristics, it’s not a Fungus.
1. Read each of the following statements. If the statement is true for a fungus, write
“T” on the line. If it is not true, write “F” on the line.
a. _____ It may have many cells.
b. _____ It has a cell membrane.
c. _____ It may have only one cell.
d. _____ It is a producer.
e _____ It has chlorophyll and can photosynthesize.
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Algae
Bacteria
Conclusion
Consumer
Control
Culture
Decomposer
Experiment
Fungi
Hypothesis
Investigation
Microorganism
Organism
Protozoan
Producer
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Single-celled
organism
Variable
Kid’s Discover Microbes Worksheet
What do you know about microbes? In the column “Before Reading,” write “true” if you
think the statement is true. Write “false” if you think the statement is false. After
reading the magazine, check your answers and see if you were correct. Write the
correct answer and the page number where you found it. If you got the answer correct,
you still need to write the page number where the answer is found.
Before Reading
Question
After Reading
1. You have billions of microbes
on your body right now.
2. One kind of microbe is
fungus.
3. It is unhealthy to eat food
containing microbes.
4. Microbes cannot live in
extreme heat or cold.
5. Bacteria make up about 1% of
your body weight.
6. Microbes produce some of
the oxygen we breathe.
7. The best protection against
infection by microbes is vaccines.
8. Antibiotics kill viruses.
9. Microbes in cookie dough with
raw eggs can make you ill.
10. The bubonic plague microbe
was responsible for killing 1/3 of
the population in Europe.
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Page Number
As you read the Microbes magazine, answer the following questions:
1. Who was the first person to look at microbes through a microscope?
__________________________________________________________________
2. Why do you need a microscope to see a microbe?
__________________________________________________________________
3. Name one microorganism van Leeuwenhoek looked at and what disease it causes.
__________________________________________________________________
4. How does the scanning electron microscope work and what is its magnification?
__________________________________________________________________
__________________________________________________________________
5. What job that microbes do “stinks?”
__________________________________________________________________
6. How do bacteria help make chocolate?
__________________________________________________________________
__________________________________________________________________
7. List three foods that use microbes to “pickle?”
a.
b.
c.
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8. Explain how cheese-makers use microbes to make their cheese.
__________________________________________________________________
__________________________________________________________________
9. Identify the six microbe menace “warning signs.”
a.
b.
c.
d.
e.
f.
10. Define “superbugs.”
__________________________________________________________________
__________________________________________________________________
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Using the diagram on pages 10 – 11, identify the microbes found in the parts of the
body.
Where are bacteria
found on the head?
Why do you close
your eyes when
you sneeze?
Why do your
armpits smell bad?
Why do so few
microbes live in
your lungs?
What “jobs” do
microbes perform
in your intestines?
Even if you
wash your hands,
where do microbes
survive?
Why do microbes
like your feet?
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