COMPLETION
1. Human activities, especially those leading to habitat loss and climate change, are likely to lead to the
extinction of between _______________ and _______________ of the world’s plant and animal species.
ANS: one-fourth; one-half
PTS: 1
DIF: Moderate
TOP: 9-0 Core Case Study
2. A 2005 report estimates the current annual rate of species extinction is at least ____________________ to
____________________ times the background rate that existed before modern humans appeared.
ANS: 100; 1,000
PTS: 1
DIF: Easy
TOP: 9-1 What Role Do Humans Play in the Extinction of Species?
3. During this century, with global climate change and other human activities, the current extinction rate
could reach ____________________ times the background rate of extinction.
ANS: 10,000
PTS: 1
DIF: Easy
TOP: 9-1 What Role Do Humans Play in the Extinction of Species?
4. According to E. O. Wilson and Stuart Pimm, at an extinction rate of 1% per year ____________________
of all animal and plant species could be gone by 2050 and ____________________ by the end of the
century.
ANS: one-fourth; one-half
PTS: 1
DIF: Moderate
TOP: 9-1 What Role Do Humans Play in the Extinction of Species?
5. A(n) ____________________ species has so few individual survivors that the species could soon become
extinct over all or most of its natural range.
ANS: endangered
PTS: 1
DIF: Easy
TOP: 9-1 What Role Do Humans Play in the Extinction of Species?
6. The rate of species loss and the extent of biodiversity loss are likely to ____________________ during
the next 50100 years as a result of the growth of the world's ____________________ and resource use
per person.
ANS: increase; human population
PTS: 1
DIF: Difficult
TOP: 9-1 What Role Do Humans Play in the Extinction of Species?
7. The species-area relationship suggests that, on average, a 90% loss of habitat causes the extinction of
____________________% of the species living in that habitat.
ANS: 50
PTS: 1
DIF: Moderate
TOP: Science Focus - Estimating Extinction Rates
8. It will take ____________________ generations for natural speciation to rebuild the biodiversity we are
likely to destroy in this century.
ANS: 200,000
PTS: 1
DIF: Easy
TOP: 9-2 Why Should We Care about the Rising Rate of Species Extinction?
9. We should act to prevent premature extinction of species, in part because they contribute to
____________________, those services that support our economies.
ANS: economic services
PTS: 1
DIF: Moderate
TOP: 9-2 Why Should We Care about Preventing Species Extinction?
10. One reason why we should work to prevent human activities from causing the extinction of other species
is that they are a vital part of the earth’s ____________________ system.
ANS: life support
PTS: 1
DIF: Moderate
TOP: 9-2 Why Should We Care about the Rising Rate of Species Extinction?
11. Burmese and African ____________________ along with several other similar species, have ended up in
the Everglades in Florida, after being released by their owners because they did not make good pets.
ANS: pythons
PTS: 1
DIF: Easy
TOP: 9-3 How Do Humans Accelerate Species Extinction?
12. Of the world's 10,000 bird species, approximately ____________________ (number) of them are
threatened.
ANS: 1,200
PTS: 1
DIF: Difficult
TOP: 9-3 How Do Humans Accelerate Species Extinction?
13. According to the US Fish and Wildlife Service, about __________ of the species listed as endangered in
the US and __________ of those in Hawaii are on the list because of threats from invasive species.
ANS: 40%; 95%
PTS: 1
DIF: Moderate
TOP: 9-3 How Do Humans Accelerate Species Extinction?
14. Biologists estimate there are now about 4 million ____________________ in Florida, Texas, and 22
other U.S. states.
ANS: European wild boars
PTS: 1
DIF: Moderate
TOP: 9-3 How Do Humans Accelerate Species Extinction?
15. DDT can ____________________ by moving up the food chain and accumulating in the fat tissues of
animals at high levels.
ANS:
bioaccumulate
biomagnify
PTS: 1
DIF: Easy
TOP: 9-3 How Do Humans Accelerate Species Extinction?
16. One possible cause of the decline in honeybee colonies could be disruption of navigation systems of
worker bees caused by ____________________ and _______________.
ANS: cell phones; cell phone towers
PTS: 1
DIF: Moderate
TOP: 9-3 How Do Humans Accelerate Species Extinction?
17. The ____________________ has the responsibility for identifying and listing endangered and threatened
oceans species under the ESA of 1973.
ANS: National Marine Fisheries Service
PTS: 1
DIF: Moderate
TOP: 9-4 How Can We Protect Wild Species from Extinction?
18. The U.S. ____________________ has the responsibility for identifying and listing endangered and
threatened species other than ocean species.
ANS: Fish and Wildlife Service
PTS: 1
DIF: Moderate
TOP: 9-4 How Can We Protect Wild Species from Extinction?
19. The ____________________ suggests we should take measures to prevent or reduce harm to the
environment and human health even if some of the cause-and-effect relationships have not been fully
established scientifically.
ANS: precautionary principle
PTS: 1
DIF: Easy
TOP: 9-4 How Can We Protect Wild Species from Extinction?
20. A new underground vault on a remote island in the Arctic is intended to preserve _______________ and
endangered plant species by storing their seeds in refrigerated, low-humidity environments.
ANS: genetic information
PTS: 1
DIF: Difficult
TOP: 9-4 How Can We Protect Wild Species from Extinction?