1. Use this drawing of a paramecium to answer the question. What is the function of the cilia marked by "X"?

to move the paramecium
to take in water and remove wastes
to control cell division
to make food from sunshine and air

2. Use this drawing of a paramecium to answer the question. What is the paramecium's body composed of?

thousands of cells
four cells
one cell and its parts
several body organ systems

3. You are looking at a pond water sample for examples of protozoa and algae. What is the best way to tell the difference between protozoa and algae?

Protozoa are larger than algae
Protozoa move and algae do not
Protozoa are not green while algae are
Protozoa have flagella and algae do not

4. What did Anton van Leeuwenhoek discover that changed what people could see and understand about the living world?

Telescopes
Cameras
Magnifying glass
Microscopes

5. Raquel placed a jar of water containing Euglena, a green plant-like protist, in a sunny window. She placed a black, opaque covering over one half of the jar. What do you think she will observe when she returns in one hour to observe water samples with

She will find more Euglena in the side of the jar in the light
She will find more Euglena in the side of the jar in the dark
She will find Euglena equally throughout the jar
She will find more Euglena at the bottom of the jar

6. What is the one thing scientists have concluded from their observations of microorgansims?

they live only in warm places
they are only waste products
they are almost everywhere
they are tiny plants

7. What important function do microorganisms have in an ecosystem?

They produce food from sunlight.
They reduce the number of large animals.
They decompose dead organisms.
They help to clean the air.

8. What does yeast do in bread dough and cheese?

It grows and releases waste products.
It absorbs sugars and changes them to starch.
It acts like a spice and flavors the food.
It breaks down into parts.

9. Viruses sometimes cause a disease because viruses ______.

take over the host cell
are made of bacteria
are not a part of the natural world
are found everywhere in the world

10. Louis Pasteur discovered that ______.

Bacteria can enter the food from the air
Heating is sometimes enough to kill bacteria
Bacteria in food comes from somewhere outside the food
Bacteria can cause food to spoil

11. By noticing that some organisms didn't grow near mold, Alexander Fleming discovered penicillin. What kind of organism does penicillin kill?

Viruses
HIV
Influenza
Bacteria

12. Bacteria are useful in protecting the environment.

They have no effect on the environment.
The cost of bacteria is too high to use it.
Some forms of bacteria break down pollutants.
No one knows what effect some bacteria have.