8.L.3.1
Name:
Date:
1. Which example shows a relationship between a living thing and a nonliving thing?
A. An insect is food for a salmon.
B. Water carries a rock downstream.
C. A tree removes a gas from the air.
butterfly.
D. A flower makes food for a
2. What is a primary role of decomposers in an ecosystem?
A. They eliminate matter by taking nitrogen from the ecosystem.
B. They eliminate matter by taking phosphorus from the ecosystem.
C. They cycle matter by returning carbon and other matter to the ecosystem.
D. They cycle matter by returning oxygen and other matter to the ecosystem.
5. If a paleontologist finds fossils of many different species existing in the same area at
approximately the same time, the paleontologist can conclude that the ecosystem in this area had
a high degree of
A. climatic variation. B. episodic speciation.
isolation.
C. biological diversity.
D. geographic
7. An ocean, a forest, and a grassy meadow are each examples of a complete ecosystem.
Complete ecosystems contain only
A. animals.
C. living and nonliving things.
B. rocks and water.
D. populations of plants and animals.
8. The complete removal of decomposers from an ecosystem will have the greatest effect on
which of the following?
A. the spread of disease
B. the availability of water
C. the recycling of nutrients
D. the distribution of organisms
9. A hurricane sweeps across a small Caribbean island, killing 50 percent of the herbivore
species on the island. Which of the following is the most immediate result?
A. a reduction in biodiversity
C. an increase in predator populations
B. an acceleration of the carbon cycle
D. a decline in decomposer populations
10. There is a limit to how large any given population can grow. Which of the following
statements best explains why a population must eventually stop growing?
A. A low female-to-male ratio develops in the population as it grows.
B. Old individuals outnumber juveniles in the population as it grows.
C. The resources available are fully used by the population as it grows.
D. Natural selection changes the gene pool of the population as it grows.
12. Which of the following is currently a primary cause of species decline worldwide?
A. habitat destruction
B. intraspecific competition
C. random mating
D. viral outbreaks
13. Continuing development of land in the southeastern United States has resulted in large
sections of forest being broken into smaller, isolated fragments. Scientists studying these forest
fragments have found that the smaller the forest fragment, the closer together birds build their
nests.
As a result of the nests being close together, which of the following will most likely happen to
the birds in a particular forest fragment?
A. Finding food will become easier for the birds.
B. Most of the birds will lay eggs later in the year.
C. Fewer birds will migrate out of the region for the winter.
D. Viral diseases will spread among the birds more quickly.
15. Two groups in Mrs. Thompson's science class made presentations about forest information
they had researched. The first group reported that some types of fungi provide water and
nutrients to a tree's roots. The second group reported that forest rodents spread fungi spores to
allow for spore reproduction. What conclusion can be drawn from the information presented by
these two groups?
A. Fungi cause disease in rodents in the forest.
B. Rodents need to be removed from the forest.
C. Having diverse organisms can spread disease in forests.
D. Having diverse organisms benefits the health of a forest.
16. How does light, temperature, and soil composition influence most land ecosystems?
A. They cause the ecosystem to become extinct.
B. They determine the types of plants and animals in the ecosystem.
C. They cause water in the ecosystem to become polluted.
17. Which biotic factor affects the number of animals in a population?
A. kinds of predators
B. amount of oxygen
C. average temperature
18. A researcher observing an ecosystem describes the amount of sunlight, precipitation, and
type of soil present. Which factors is the researcher most likely describing?
A. biotic factors in a forest
B. biotic factors in a tundra
C. abiotic factors in a prairie
D. abiotic factors in an ocean
19. A population could best be represented by all of the
A. acorn barnacles on a rock
B. different species of fish in a bay
C. animals found along a sandy beach
D. organisms in a pond
21. All the brook trout in a stream constitute
A. an ecological succession
B. a population
C. a habitat
D. a food chain
22. Which level of biological organization includes the greatest total number of species?
A. community
B. ecosystem
C. population
D. biosphere
23. In a self-sustaining ecosystem, which component cannot be recycled because it is lost from
food chains and becomes unavailable?
A. carbon
B. nitrogen
C. water
D. energy
24. One characteristic common to bacteria, algae, protists, fungi, vascular plants, and humans is
that they are
A. members of the biosphere
B. heterotrophic organisms
C. abiotic factors
D. multicellular organisms
25. An ecosystem is not considered to be self-sustaining if
A. there is interaction between biotic and abiotic factors
B. some of its living systems incorporate energy into organic compounds
C. cycling of materials occurs between organisms and their environment
D. it lacks a constant supply of energy