Name ________________________________Date _________________ Period ______________
Ecological Organization
Modified True/False
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true.
____
1. The statement, “the cowbird can tolerate a wide range of temperatures,” characterizes the cowbird’s habitat.
_________________________
____
2. A bird fluffs its feathers to trap warm air close to its body. The temperature of the air next to the bird’s skin
is a(n) abiotic factor. _________________________
____
3. The species interaction most frequently represented in a food chain is mutualism.
_________________________
____
4. An ecologist who is studying the relationships among the dominant communities in a geographical region is
studying an ecosystem. _________________________
____
5. Any biome in which the annual rate of evaporation exceeds the rate of precipitation is classified as temperate.
_________________________
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
6. The combined portions of Earth in which all living things exist is called the
a. biome.
b. community.
c. ecosystem.
d. biosphere.
____
7. All of the members of a particular species that live in one area are called a(an)
a. biome.
b. population.
c. community.
d. ecosystem.
____
8. Which of the following descriptions about the organization of an ecosystem is correct?
a. Communities make up species, which make up populations.
b. Populations make up species, which make up communities.
c. Species make up communities, which make up populations.
d. Species make up populations, which make up communities.
____
9. The simplest grouping of more than one kind of organism in the biosphere is
a. a population.
b. a community.
c. an ecosystem.
d. a species.
____ 10. The lowest level of environmental complexity that includes living and nonliving factors is the
a. biome.
b. community.
c. ecosystem.
d. biosphere.
____ 11. If the global warming trend continues and permafrost under the tundra melts, what biome would you predict
would replace it?
a. boreal forest
c. temperate grassland
b. temperate forest
d. desert
____ 12. Why does Earth have three main climate zones?
a. Warm air rises at the equator and cold air sinks over the poles causing an unequal
distribution of heat over Earth.
b. There are differences in latitude and, thus, the angle of heating from the sun.
c. Continents and other landmasses physically interfere with global heat distribution.
d. The Earth rotates and affects the major ocean currents.
____ 13. The symbiotic relationship between a flower and the insect that feeds on its nectar is an example of
a. mutualism because the flower provides the insect with food, and the insect pollinates the
flower.
b. parasitism because the insect lives off the nectar from the flower.
c. commensalism because the insect does not harm the flower and the flower does not benefit
from the relationship.
d. predation because the insect feeds on the flower.
____ 14. Which two biomes have the least amount of precipitation?
a. tropical rain forest and temperate grassland
b. tropical savanna and tropical dry forest
c. tundra and desert
d. boreal forest and temperate woodland and shrubland
Short Answer
15. Discriminate between weather and climate, and summarize the distinctions between them.
Problem
A scientist wrote the following summary of her observations:
Milkweed is a plant commonly found throughout fields and pastures and along roadsides in eastern and
central North America. It gets its name from the milky white sap that oozes when the plant is broken or cut.
Milkweed plants bloom in June and July. When fertilized, the flowers form large seedpods that open in the fall.
The following observations were taken from a scientist's field study of milkweed plants from spring through fall.
In the summer, the sugary nectar secreted by the milkweed's flowers attracts many bees, butterflies, moths,
and a variety of smaller insects that carry away pollen when they depart. Milkweed nectar seems to be the major
source of nutrition for several species of small moths, flies, mosquitoes, and ants. Monarch butterflies, which
visit in large numbers, lay their eggs on milkweed plants, and the hatching caterpillars feed on the leaves. As fall
approaches, milkweed bugs begin to attack the developing seeds, and milkweed beetles eat the foliage.
Aphids, which suck milkweed sap, are found throughout the year. Crab spiders do not feed on the plant
itself, but rather on most of the insects that visit the plant. In the two to three weeks while the milkweed plants
are in bloom, successful adult female crab spiders may increase ten times in mass before laying their eggs on the
inner surface of leaves. Some species of flies and wasps, which feed on crab spider eggs, visit the plants
periodically. Harvestmen, also known as "daddy longlegs," recover the remains left by predators.
16. Based on the scientist's observations, write a possible hypothesis about the effects of crab spiders on the
survival of the milkweed plant.
.
.
17. How would you describe the symbiotic relationship between the milkweed plant and aphids?
.
.
18. From the scientist's data, which abiotic factor affects milkweed. Explain how the data support your inference.
.
.
19. What would you call a patch of milkweed plants plus all the organisms that visit or live on the plants?
Other
USING SCIENCE SKILLS
Average Rainfall and Temperature of Earth’s Biomes
Biome
Average Yearly
Rainfall
Tropical Rain Forest
400 cm
Tropical Dry Forest
250–300 cm
Temperate Forest
75–125 cm
Boreal Forest
35–75 cm
Tropical Savanna
150 cm
Desert
Less than 25 cm
Temperate Grassland
25–75 cm
Tropical Woodland
and Scrubland
Less than 50 cm
Tundra
30–50 cm
Average
Temperature
Climate Zone
Daytime: 34ºC
Nighttime: 20ºC
Dry season: 32ºC
Wet season: 20ºC
Summer: 28ºC
Winter: 6ºC
Summer: 14ºC
Winter: –10ºC
Dry season: 34ºC
Wet season: 16ºC
Summer: 38ºC
Winter: 7ºC
Tropical
Summer: 30ºC
Winter: 0ºC
Summer: 20ºC
Winter: 10ºC
Temperate
Summer: 12ºC
Winter: –26ºC
Temperate and
polar
Tropical
Mostly temperate
Mostly temperate
Mostly tropical
Tropical and
temperate
Temperate
Figure 4-2
20. Using Tables and Graphs Which climate zone listed in Figure 4-2 includes the most biomes?