Name ______Period ______
Organism Relationships Worksheet Packet
In Yellowstone National Park , the populations of wolves and moose rise and fall in cycles. Use the graph to answer questions 1 through 8.
1. What variable is plotted on the x-axis? ______
2. What variable is plotted on the y-axis? ______
3. How did the Moose population change between 1965 and 1975? ______
4. What happened to the wolf population from 1973 through 1976 ______
5. Infer how the change in the moose population might have led to the change in the wolf population ______
______
6. Draw a conclusion about one likely cause of the dip in the moose population between 1975 and 1980. ____
______
7. Predict how a disease in the wolf population during one year might affect the moose population the next year. ______
8. What type of relationship do the wolves and moose in Yellowstone have?
a. parasite / hostb. predator / preyc. competitor / predatord. symbiosis / prey
9. How does the camouflage of a walking stick insect affect the population size of that species?______
Page 2
10. Symbiosis is going on right under your nose – or above it. Microscopic mites called Demodex folliculorum live at the base of human eyelashes, where they feed on tiny bits of dead skin and body oils. What type of symbiotic relationship is this?
a. parasitismb. mutualism Six eyelash mites feast head-down at
c. commensalismd. predatorism the base of a single human eyelash.
11. Explain why a parasite doesn’t usually kill its host organism ______
______
12. Cows have a multi-chambered stomach called a rumen. Inside these chambers are bacteria that help break down the cellulose in alfalfa and grass. What type of symbiotic relationship is this?
a. parasitismb. commensalismc. symbiosismd. mutualism
13. Some of your classroom plants are dying. Others that you planted at the same time and cared for in the same way are growing well. When you look closely at the dying plants, you see tiny mites on them. Which symbiotic relationship is likely occurring between the plants and the mites? Explain. ______
______
14. A prairie dog, a hawk, and a badger all are members of the same
a. nicheb. communityc. speciesd. population
15. All of the following are examples of limiting factors for populations except
a. spaceb. foodc. timed. weather
17. Which of these relationships is an example of parasitism?
a. a bird building a nest on a tree branchb. a bee pollinating a peach orchard
c. a flea living on a cat’s bloodd. ants protecting a tree that produces ant food
18. True or False An organism’s specific role in its habitat is called its niche.
19. True or False The struggle between organisms for limited resources in called mutualism.
20. True or False A parasite lives on or inside its predator.
21. True or False Since milkweed and a monarch butterfly both benefit from their relationship, this is called
commensalism.
Page 3
Ecologists from the Utah State Division of Wildlife Resources collected the following data during a 30-year study of deer populations in Northern Utah:
Year / 0 / 5 / 10 / 15 / 20 / 25 / 30Population / 15,000 / 30,000 / 65,000 / 100,000 / 40,000 / 25,000 / 10,000
22. Make a line graph using the data in the table. Plot years on the horizontal axis and population on the vertical axis.
23. In which year did the deer population reach its highest point? ______Its lowest point? ______
24. In year 16 of the study, Northern Utah experienced a very severe winter. How might this have affected the deer population? ______
25-27 Label each of these relationships as predator/prey, parasitism, commensalism, or mutualism
Humans are often responsible for destroying a species. Imagine a situation like this. An exotic flying ant from South America is attacking orange trees in California and Florida. The citrus growers buy a new insecticide to kill the ants. All citrus trees are sprayed. All of the ants die, but honeybees and bumblebees in California and Florida are also killed. Such bees are responsible for pollinating orange trees. If bees COULD NOT be imported from other areas, what would be the result for the citrus crop, and for people? List 3 direct or indirect results.
28. ______
29. ______
30. ______
Page 4
Eco-Search
N / E / C / F / O / E / F / N / O / I / T / E / L / E / P / M / O / C / E / C / OE / T / H / O / O / N / O / E / R / E / Y / R / T / R / N / R / E / D / I / F / C
G / R / A / E / M / O / O / R / E / O / T / T / E / A / D / E / R / P / N / Y / S
O / M / I / T / S / E / D / O / T / E / I / Y / N / O / R / T / R / I / S / G / U
R / A / I / N / I / R / C / W / L / C / N / I / L / T / N / A / L / G / M / O / D
T / E / R / T / T / B / H / R / E / O / U / S / I / E / H / C / I / N / Y / L / I
I / H / M / L / I / E / A / A / H / B / M / M / M / A / E / U / N / E / E / O / R
N / I / S / R / S / N / I / H / S / T / M / N / I / U / B / I / O / T / I / C / U
M / S / I / L / A / S / N / E / M / M / O / C / T / E / T / T / I / M / C / E / C
N / C / N / E / R / S / E / H / N / R / C / A / I / H / E / U / T / S / I / O / E
H / R / A / N / A / H / D / O / I / T / I / T / N / U / S / U / A / E / T / B / M
A / L / G / E / P / I / B / V / A / A / B / O / G / E / I / M / D / L / O / R / A
E / B / R / R / N / R / N / H / M / E / T / S / Y / S / O / C / E / K / I / A / D
I / T / O / G / A / E / E / R / E / H / A / T / I / B / A / H / R / I / B / S / A
T / A / Y / C / E / L / T / N / O / I / T / A / L / U / P / O / P / L / A / C / M
ABIOTICFOOD CHAINPOPULATION
BIOTICFOOD WEBPREDATION
COMMENSALISMHABITATPREY
COMMUNITYHEATRAIN
COMPETETIONLIMITINGSHELTER
ECOLOGYMUTUALISMSUN
ECOSYSTEMNICHE______
ENERGYORGANISM______
ENVIRONMENTPARASITISM______