Download Ch. 9 Notes

Chapter 9
Balance Within Ecosystems
Pages 311-339
1. An example of captive
breeding is when zoos keep
condors for mating.
Lesson 4
2. If all members of a species
disappear from Earth, the
species is said to be extinct.
Lesson 3
3. The series of changes that
occur in an area where the
ecosystem has been disturbed
but soil and organisms still exist
is secondary succession.
Lesson 1
4. An example of how humans
can harm an ecosystem is
desertification.
Lesson 2
5. The number of different
species in an area is called
biodiversity.
Lesson 3
6. Organisms that survive a
changing ecosystem have
adaptations that help them in
new conditions.
Lesson 1
7. The first species to populate
an area after primary succession
are pioneer species.
8. Pioneer species are carried to
areas by wind and water.
9. A species that does not naturally
occur in an area or brought in by
people is a nonnative species.
10. A species that is a major
influence on the survival of other
species in an ecosystem is a
keystone species.
11. Which two areas have the
most diverse ecosystems?
Rain forests and Coral reefs
12. Two human activities that
lead to extinction are hunting
and habitat destruction.
13. A diverse gene pool helps ensure
that individuals in species will pass a
variety of traits to their offspring.
14. Setting aside a marsh as a
wildlife refuge to protect
biodiversity is an example of
habitat preservation.
15. Illegal killing or removal of
wildlife from their habitats is
poaching.
16. The study of where
organisms live and how they got
there is biogeography.
17. The movement of organisms
from one place to another is
dispersal.
18. An exotic species is an
organism that is carried into a
new location by people.
19. As the Earth’s plates move,
the continents move with them
in a process called continental
drift.
20. What are two physical
barriers that limit distribution of
species? Water and Mountains
21. Why might species in a
population increase rapidly?
Limited predators
22. What kinds of scientists
might be involved in protecting
biodiversity? Biologists
23. The greatest genetic
diversity exists among species of
unicellular organisms.
24. Species that lack a diverse
gene pool are less able to adapt
to and survive changes in the
environment.
25. Species that could become
endangered in the near future
are called threatened species.
26. Decomposers break down
dead plants and animals and this
adds nutrients to the soil.
27. Habitat loss is a much more
important cause of extinction for
birds than mammals because
they rely on trees.
28. Poaching may be a more
important threat to mammals
than birds because birds are
harder to catch.
29. What are two endangered or
threatened species you have
heard about? giant pandas and
bald eagles
30. Brown pelicans are no longer
endangered because of a ban in
1972 on a pesticide called DDT.