Life Science Unit 1: Ecology

Directions: Determine the best solution to each question and record your answer on your scantron form.

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1)  The characteristics of a praying mantis allow it to be camouflaged by the green stems of plants. While camouflaged, a praying mantis can feed on other insects that inhabit or feed on a plant. If a praying mantis feeds on natural predators of a plant, what type of relationship is occurring between the praying mantis and the plant?

A  camouflage

B  dompetition

C  mutualism

D  parasitism

2)  Which organism would best fit in the empty spot in the food web shown above?

A  a prairie dog

B  a turkey vulture

C  a fox

D  a blue jay

3)  Which of the following answer choices correctly arranges the levels of environmental organization in order of smallest to largest?

A  organism, population, community, ecosystem, biosphere

B  organism, population, community, biosphere, ecosystem

C  organism, community, population, ecosystem, biosphere

D  biosphere, ecosystem, community, population, organism

4)  What is the primary source of the energy that flows through food webs on land?

A  producers

B  sunlight

C  oxygen

D  photosynthesis

5)  If fish in a river begin to die because of pollution, what may happen to the river ecosystem?

A  All organisms in the ecosystem will be affected in some way.

B  All species of organisms in the ecosystem that rely on fish for food will starve and die.

C  The organisms that eat fish will reproduce faster.

D  The abiotic factors, but not the biotic factors, in the ecosystem will change.

6)  Which of the following statements best describes a food web?

A  Many individual organisms of the same species that live in the same space and that share resources.

B  A system that is made up of a community of organisms and their environment.

C  A black bear eats fruit and then spreads the fruit’s seeds through its excretions.

D  All life is connected by the transfer of energy and matter among organisms and their environment.

7)  The graph shows the number of seaside sparrows and little marsh crabs in a salt marsh habitat on Georgia’s coast over a five year period. In which year was there a disease that killed off most of the cordgrass, a source of food and shelter for the animals in the marsh?

A  year 1

B  year 2

C  year 3

D  year 4

8)  Which of the following is an abiotic part of a river that will affect the organisms that currently live in or near the river?

A  the diversity of the life in the river

B  the speed at which the water flows

C  the predators living near the river

D  the direction in which the water flows

9)  In which area are you most likely to find plants that can tolerate water that has a constantly changing salt content?

A  a freshwater stream

B  an estuary

C  a pond

D  a coral reef

10) The graph shows the temperature zones of the ocean. Wei-lin is studying the role of sardines in ocean ecosystems. She learns that sardines survive only in water that is between 14°C and 20°C. At what depth are sardines most likely found?

A  between the surface and 300 m below the surface of the ocean

B  between 5 and 25 m below the surface of the ocean

C  between 400 and 600 m below the surface of the ocean

D  between 700 and 1,200 m below the surface of the ocean

11) Over a long period of time, a lake ecosystem can become a forest ecosystem. The decomposition of dead plant and animal matter is a part of this process. Which of the following organisms would most likely be responsible for decomposing the dead plant and animal matter in a lake?

A  bacteria

B  clams

C  grasses

D  snails

12) Scientists involved in a field study of a biome produced the graph below. The line represents temperature and the bars represent precipitation. Which of the following is a valid conclusion about the biome?

A  The biome is a rainforest.

B  The annual variation in temperature (from high to low) is
about 25°C.

C  The biome receives the same amount of rainfall each month.

D  The biome has little plant life.

13) Which of the following statements about the relationship between organisms and the environment is correct?

A  When an environment changes gradually, the organisms within the environment remain unchanged.

B  When an environment changes gradually, all of the organisms die and new organisms that are suited to the new environmental conditions move in.

C  When an environment changes gradually, all of the organisms adapt to the new environmental conditions and continue to thrive.

D  When an environment changes gradually, some organisms may adapt, some organisms may die, and some new organisms may move in.

14) Which of the following statements describes one way that plants depend on other organisms?

A  Plants get energy from the waste products of animals.

B  Animals get energy from the plants that the animals eat.

C  Bacteria fix nitrogen into forms that plants can use.

D  Animals use plants and plant parts to make nests.

15) Nitrogen fixation occurs when ______.

A  bacteria in the soil change nitrogen gas into forms that plants can use.

B  bacteria in the soil release nitrogen gas into the atmosphere.

C  bacteria in the soil take up nitrogen from the soil.

D  bacteria in the atmosphere change nitrogen gas into forms animals can use.

16) Cycles in nature involve the recycling of matter. Which of the following processes is a part of the water cycle?

A  decomposition

B  transpiration

C  photosynthesis

D  combustion

17) The diagram shows the carbon cycle. Which of the following processes is primarily involved in releasing carbon into the soil?

A  combustion

B  decomposition

C  photosynthesis

D  respiration

18) Limiting factors determine an area’s carrying capacity because ______.

A  the number of animals is limited.

B  ecosystems are small.

C  animals need resources to survive.

D  the number of animals is unlimited.

19) An environmental study reporting on the way temperature, water quality, and minerals affect the animals in a salt marsh would be considering which level of organization?

A  individual organism

B  population

C  community

D  ecosystem

Use the diagram below to answer questions 20 and 21.

20) Three organisms on the food web have arrows pointing away from them and no arrows pointing toward them. They are ______.

A  omnivores

B  herbivores

C  decomposers

D  producers

21) Three organisms on the food web have arrows pointing toward them but no arrows pointing away from them. This is because ______.

A  they make their own food

B  they give energy to others

C  nothing shown eats them

D  they need no energy

22) The arrows on the food web show that______.

A  prairie dogs eat grass

B  deer eat prairie dogs

C  squirrels eat grass

D  squirrels eat coyotes

23) What does the arrow between the grasshopper and the coyote represent?

A  energy flowing from producers to consumers

B  energy flowing from consumers to producers

C  energy flowing from the coyote to the grasshopper

D  energy flowing from the grasshopper to the coyote

24) The speed of water is an important abiotic factor in a freshwater ecosystem because

A  a tributary has different plants than a river.

B  faster water has a higher salt content.

C  animals must adapt so they are not washed away.

D  animals cannot live in fast-moving water.

Use the diagram below to answer questions 25 and 26.

25) Which label is represented by letter B?

A  Oceanic zone

B  Benthic zone

C  Neritic zone

D  Intertidal zone

26) Which label is represented by letter D?

A  Oceanic zone

B  Benthic zone

C  Neritic zone

D  Intertidal zone

The graphs below show the population growth for two populations. Use these graphs to answer the questions 27and 28.

27) After 2 days, which population has more individuals?

A  Population A has more individuals.

B  Population B has more individuals.

C  The populations are the same.

D  There is not enough information to determine the answer.

28) On day 10, which statement is probably true?

A  Population B is larger than population A.

B  Population A is the same as it was on day 5.

C  Population A and B are the same.

D  Population B is the same as it was on day 5.

29) Which biome is most likely found in the region described by the graphs below?

A  Tundra

B  Tropical Rainforest

C  Desert

D  There is not enough information to determine the answer.

30) What type of organisms are found at the primary consurmer level?

A Herbivores and Carnivores

B Carnivores and Omnivores

C Omnivores and Herbivores

D Carnivores and Decomposers

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WRITE YOUR RESPONSES TO THE SHORT ANSWER QUESTIONS ON A SEPARATE SHEET OF PAPER

Directions: Constructed Responses: Choose two GPS standards and answer the writing prompt in a 4-6 sentences that demonstrates your mastery of the standard S7L4: Students will examine the dependence of organisms in their environment.

Question 1 S7L4c: Directions: Answer parts A and B in a paragraph of 4-6 sentences paragraph.

A)  Explain how the sheephead minnow population would change if the grass shrimp were to be eliminated from this food web.

B)  How might the otter population be affected if the grass shrimp were to be eliminated from the food web.

Question 2:S7L4 d.

Choose one of the following relationships and explain which type of symbiosis is involved AND why. Be specific.

1.  ticks feeding on a dogs blood

2.  bees transporting pollen from flowers while they collect nectar

3.  pilot fish swimming under sharks and eating food that the shark leaves behind

Question 3: S7L4. e. Describe the characteristics of Earth’s major terrestrial biomes (i.e. tropical rain forest, savannah, temperate, desert, taiga, tundra, and mountain) and aquatic communities (i.e. freshwater, estuaries, and marine).

A particular biome experiences average rainfall of 9 to 25 cm per year and has an average temperature of -30̊ C to 10̊ C. A friend of yours says that this represents a desert biome. Is your friend correct or incorrect? Explain why or why not.

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Life Science (Grade 7) Unit 1 Almost There Test/Post-Test

Ecology ANSWER KEY

Problem / Standard/
Element / Answer / DOK Level /
1. / S7L2D / C
2. / S7L4A / D
3. / S7L4A / A
4. / S7L4B / B
5. / S7L4C / A
6. / S7L4B / D
7. / S7L4C / B
8. / S7L4C / B
9. / S7L4E / B
10. / S7L4E / C
11. / S7L4C / A
12. / S7L4E / B
13. / S7L4C / D
14. / S7L4D / C
15. / S7L4A / D
16. / S7L4C / B
17. / S7L4A / B
18. / S7L4C / C
19. / S7L4C / D
20. / S7L4A / D
21. / S7L4A / C
22. / S7L4A / A
23. / S7L4B / D
24. / S7L4E / C
25. / S7L4E / C
26. / S7L4E / B
27. / S7L4C / B
28. / S7L4C / D
29. / S7L4E / C
30. / S7L4B / C
Short Answer Questions
31. / S7L4A
32. / S7L4B
33. / S7L4C
34. / S7L4D
35. / S7L4E

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