Name ______________________________ Date ______________
Ecosystems
1. Which of the following living things in the pond system uses the energy from sunlight to make
its own food?
A. Insect
B. Frog
C. Water Lily
D. Small Fish
2. In the pond, small fish eat algae. What two predators might eat the small fish in the pond
system?
A. Insect and Frog
B. Frog and Algae
C. Bacteria and Algae
D. Large fish and Heron
 July, 2002 Jackson County Intermediate School District
Permission is given to Jackson County Schools to reproduce these assessments for classroom use.
3. If all of the small fish in the pond system died from a disease, what would happen to the algae
in the pond?
a. The algae would die because the fish are needed to keep them healthy.
b. The heron would start eating the algae (even though they didn’t eat the algae before).
c. The algae would increase in number because they are no longer in competition with the
small fish.
d. The algae would increase in number because they are no longer a food source for one of the
populations in the pond.
4. Describe what would happen to the population of large fish if all the small fish died, and
explain why this would happen.
A farmer just fertilized the field around the pond, when a large rainstorm washed some
fertilizer off the field and into the pond.
5. What would happen to the algae in the pond system after one month?
6. Why do you think the fertilizer would affect the algae this way?
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7. How do you think this will affect the natural balance of the pond ecosystem later? Make
sure to give support for your answer.
Many farms are being sold or taken out of cultivation. Larry’s father quit farming. He sold one
field to a builder who is going to put houses on the land. He left another field vacant, to be used
for deer hunting, since it was next to a state forest.
8. Describe how the wildlife and plants will change in each field over the next few years.
In the field left vacant:
In the field where houses are built:
9. How can the change in these habitats affect the neighboring ecosystem on the hunting
grounds.
a. The deer will no longer come close to the area now occupied by humans.
b. The deer will no longer come into the field to feed.
c. The hunters will need to go deeper into the forest because of new zoning laws enacted
because of development.
d. All of the above.
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10. When people started moving into the houses, more and more wastes were produced where
the field used to be. Describe several different types of wastes produced by people living in
houses, and the effects each may have on the environment.
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Use the following story to answer questions 11 and 12.
On a rocky coast off the coast of Lake Michigan Sally found some stones at the edge of the lake.
She observed animals known as barnacles. These small crab-like and shrimp-like creatures spend
their entire adult lives attached to one spot. When Sally looked closely, she noticed two striped
layers on the stones. The narrow top layer consisted of small barnacles with smooth shells. The
wide bottom layer consisted of large white barnacles with ridged shells.
That night she did some reading and found that what she observed was an example of
competition. She came to the conclusion that small barnacles can live anywhere on the rock.
However, the big barnacles crowd them out. Small barnacles live only where big barnacles
cannot. Because of competition small barnacles have fewer locations they can live in comparison
to larger barnacles.
11. How does competition affect the size of the small barnacle population?
a.
b.
c.
d.
The small barnacle population increases.
The small barnacle population remains the same.
The small barnacle population became extinct.
The small barnacle population decreases.
12. How would the number of small barnacles change if all of the big barnacles were killed by
disease? Explain your answer, and give another example of competition.
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13. Your dog has contracted fleas. The fleas and your dog have what kind of relationship?
a.
b.
c.
d.
mutually beneficial
competition
parasite
predator
14. You are out in your garden and you notice a humming bird flying from one flower to another
collecting nectar. The humming bird and the flower have what kind of relationship?
a.
b.
c.
d.
competition
parasite
mutually beneficial
predator
15. In the space below describe why the relationship between the humming bird and the flower is
so important. Make sure to give support for your answer. Describe another relationship that
is similar to the humming bird and the flower.
16. You and your family have taken your boat out onto Lake St. Clair for a weekend of fun.
When it is time to go home on Sunday you take your boat out of the water and notice tiny
clam-like organism on the bottom of your boat. You do not think anything about it. You go
home and put your boat in a smaller inland lake the next weekend. The small clam-like
organism will have what kind of relationship with the organisms in the smaller lake?
a.
b.
c.
d.
mutually beneficial
non-native species
predator
producer
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17. You are walking through a beautiful field with a wide variety of flowers. You think about the
relationships that these flowers have with each other. Based on what you know, these flowers
have what kind of a relationship?
a.
b.
c.
d.
population
species
community
biodiversity
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