module59REVIEW

In this module, we have seen that declines in biodiversity are happening at a rate that may indicate the start of a sixth mass extinction. At the genetic level, a loss of diversity is a concern because it places species under the threat of inbreeding depression that can cause population declines. We have observed declines in the genetic diversity of both wild species and domesticated species such as crops and livestock. At the species level, we have learned that major groups of organisms, including mammals, fish, and amphibians, have all experienced extinctions and contain large groups that are threatened or near-threatened. This global decline in species affects the functioning of ecosystems and reduces the intrinsic and instrumental values that these ecosystems provide. In the next module, we will examine the many causes of these declines in biodiversity.

Module 59 AP® Review Questions

Question 1

1. In a major extinction event, what is the minimum percentage of species that goes extinct?

  1. 25 percent

  2. 40 percent

  3. 50 percent

  4. 75 percent

  5. 90 percent

Question 2

2. What factor has played the largest role in decreased diversity of domesticated species?

  1. A focus on increased yields

  2. The use of genetic engineering

  3. The adaptation to specific growing environments

  4. The decreased number of pests

  5. Increased seed storage efforts

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Question 3

3. Which group of organisms has had the greatest number of extinctions since 1500?

  1. Birds

  2. Amphibians

  3. Mammals

  4. Reptiles

  5. Fish

Question 4

4. The intrinsic value of an ecosystem

  1. is the total monetary worth of its features.

  2. is based on the goods the ecosystem produces.

  3. considers the potential benefits that could be discovered in the ecosystem.

  4. is the value it has independent of humans.

  5. is the function of an ecosystem that humans cannot replicate.

Question 5

5. Which is NOT a category of instrumental value?

  1. Regulating services

  2. Resilience

  3. Provisions

  4. Cultural services

  5. Diversity