Chapter 7 Study Guide (Environmental Science)


The variety of life across all levels of ecological organization.

Species Diversity

The number or variety of species in a particular region.

Genetic Diversity

The differences in DNA among individuals within species and populations.

Ecosystem Diversity

The number and variety of ecosystems within a given area.


The disappearance of a particular population from a given area, but not of the entire species globally.

Endangered Species

One that is at serious risk of extinction.

Threatened Species

One that is likely to become endangered soon throughout all or part of its range.

Habitat Fragmentation

The division of a habitat into smaller patches.


The illegal capture or killing of an organism.

Endangered Species Act (ESA)

The major law that protects biodiversity.

Captive Breeding

The process of breeding and raising organisms in controlled conditions.

Species Survival Plan (SSP)

A plan carried out by zoos and aquariums to protect a species.

Biodiversity Hotspot

An area that both supports an especially high number of endemic species and is rapidly losing biodiversity.


Found in one area of the world.

Species generates new species, adding to species diversity, whereas ________ decreases species diversity.


Which type of biodiversity helps a species adapt to changing environmental conditions?

Genetic Diversity

What type of biodiversity is demonstrated by a seashore of rocky and sandy beaches, forested cliffs, and ocean waters?

Ecosystem Diversity

Which statement about species diversity is true?

Species Diversity is highest near Earth's poles.

Why don't scientists know exactly how many species are on Earth?

Many species are tiny and easily overlooked, many organisms are hard to tell apart, and some areas remain relatively unexplored.

So far, scientists have identified and described 1.7 to 2 million species. The best-educated guesses estimate that the total number of species on Earth is

5 to 30 million.

A wetland naturally purifying water is an example of a(n)

Ecosystem Service

Travelers visiting the Everglades National Park to picnic, camp, and view the alligators and cypress trees would be best described as


What are the benefits of ecotourism?

Helps people appreciate nature, promotes wildlife and habitat conservation, and provides economic benefits to local people.

Biodiversity can be a direct source of ____________ for places such as Costa Rica's rain forests, Kenya's game reserves, Florida's coral reefs, and Kentucky's caves.


Today, species loss seems to be


A species that is likely to become endangered throughout all or part of its range is called a(n)

Threatened Species

The Living Planet Index tracks

Species Decline.

___________ species are non-native organisms that increase their populations rapidly, spread, and displace native species, thus reducing biodiversity.


The Siberian tiger is large in size, few in number, long-lived, and raises few young in its lifetime. It is particularly vulnerable to population reduction by


In some areas, biodiversity is reduced by ___________, the illegal capture or killing of an organism.


Sometimes, many nations join together to protect biodiversity by making an agreement under international law. These agreements are called


Peregrine falcons, bald eagles, and other birds affected by the pesticide DDT had their populations restored largely due to

The Convention on Biological Diversity.

The protection of tigers in many countries and the increased market for "shade-grown" coffee were accomplished primarily by

International Treaties

The main goal of Species Survival Plans is to

manage, protect, and reintroduce threatened and endangered species.

One of the final goals of a captive breeding program is to

reintroduce the organisms to the wild.

Zoos turned their initial population of 91 golden lion tamarins into a population of about 500. Then 150 golden lion tamarins were released into the wild. This is an example of a successful

Captive Breeding Program.

Many conservation biologists support the idea of prioritizing habitat preservation is special areas of the world that possess exceptionally high numbers of species found nowhere else. These areas are called

Biodiversity Hotspots

The country of Surinam is part of an agreement that has earned it about $15 million in exchange for preserving extensive areas of rain forest. This agreement is an example of a(n)

Conservation Concession

Wildlife corridors can help solve and prevent

Habitat Fragmentation

Explain why scientists don't know exactly how many species live on earth.

First, some areas of Earth remain relatively unexplored. Second, many species are tiny and easily overlooked. Third, many organisms are extremely difficult to identify and tell apart from other species.

What steps could be taken to combat the effects of habitat fragmentation?

Humans can improve land-use practices to reduce the amount of land affected by logging, road building, farming, and other activities. When land does need to be cleared, care should be taken to leave areas that connect similar habitats to one another so th