Interactions in Ecosystems
Study Guide B
Answer Key
SECTION 1. HABITAT AND NICHE
1. a habitat is all of the biotic and abiotic
factors in the area where an organism
lives, while a niche includes all physical,
chemical, and biological factors that a
species needs to survive, stay healthy, and
reproduce
2. habitat: food, other lions, trees, watering
hole, wildebeest, zebra, sand, temperature,
grass, savanna; niche: all of the above
plus hunting behavior
3. a principle that states that when two
species are competing for the same
resources, one species will be better suited
to the niche and the other species will
either be pushed into another niche or
become extinct
4. one competitor is pushed out of a niche by
another competitor, niche partitioning
(resources are divided among
competitors), evolutionary response
(divergent evolution occurs)
5. species that occupy similar niches but live
in different geographical regions
6. ecological equivalents live in two
different geographic locations and
therefore do not compete for the same
resources
7. a habitat is an area or environment where
an organism or ecological community
normally dwells, or lives
8. two species that use the same resources
in the same way compete together; the
species that is less suited (less well-
adapted) will be pushed out of
(excluded from) the niche or become
extinct
9. in math an equivalent refers to two sets
that have identical or corresponding
parts; in a similar way, ecological
equivalents are two species that occupy
identical niches but occur in different
regions
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology Interactions in Ecosystems
Study Guide B
Name ______________________________ Class ___________________ Date __________________
Section 1: Habitat and Niche
Study Guide B
KEY CONCEPT
Every organism has a habitat and a niche.
VOCABULARY
MAIN IDEA: A habitat differs from a niche.
1. What is the difference between an organism’s habitat and its ecological niche?
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2.
Determine which ecological factors are a part of a lion’s niche and which are a part
of a lion’s habitat by placing the above items in the correct column.
MAIN IDEA: Resource availability gives structure to a community.
3. What is competitive exclusion?
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habitat competitive exclusion
ecological niche ecological equivalent
food trees zebra grass
hunting
behavior watering hole sand savanna
other lions wildebeest temperature
Habitat Niche
© Houghton Mifflin Harcourt Publishing Company
Holt McDougal Biology 1 Interactions in Ecosystems
Study Guide B Section 1: Habitat and Niche
Name ______________________________ Class ___________________ Date __________________
Study Guide B continued
4. What are the three possible outcomes of competit...
