Unit 2

Question 1

Biodiversity

Answer 1

The diversity of life forms in an environment.

Question 2

Genetic diversity

Answer 2

A measure of the genetic variation among individuals in a population.

Question 3

Population bottleneck

Answer 3

When a large population declines in number, the amount of genetic diversity carried by the surviving individuals is greatly reduced.

Question 4

Species diversity

Answer 4

The number of species in a region or in a particular ecosystem.

Question 5

Habitat diversity

Answer 5

The variety of habitats that exist in a given ecosystem.

Question 6

Specialists

Answer 6

Species that only live under a narrow range of biotic or abiotic conditions

Question 7

Generalists

Answer 7

Species that can live under a wide range of biotic or abiotic conditions.

Question 8

Ecosystem diversity

Answer 8

The variety of ecosystems that exist in a given region.

Question 9

Species richness

Answer 9

The number of different species in a given area.

Question 10

Species evenness

Answer 10

The relative proportion of individuals within the different species in a given area.

Question 11

Ecosystem services

Answer 11

The processes by which life-supporting resources such as clean water, timber, fisheries, and agricultural crops are produced.

Question 12

Provision

Answer 12

A good produced by an ecosystem that humans can use directly.

Question 13

Aquaculture

Answer 13

The farming of fish, shellfish, and seaweed.

Question 14

Island biogeography

Answer 14

The study of how species are distributed and interacting on islands.

Question 15

Species-area curve

Answer 15

A description of how the number of species on an island increases with the area of the island.

Question 16

Ecological tolerance (Fundamental niche)

Answer 16

The suite of abiotic conditions under which a species can survive, grow, and reproduce.

Question 17

Realized niche

Answer 17

The range of abiotic and biotic conditions under which a species actually lives.

Question 18

Geographic range

Answer 18

Areas of the world in which a species lives.

Question 19

Mass extinction

Answer 19

A large number of species that went extinct over a relatively short period of time.

Question 20

Periodic disruption

Answer 20

Occurring regularly, such as the cycles of day and night or the daily and nightly cycle of the moon’s effects on ocean tides.

Question 21

Episodic disruption

Answer 21

Occurring somewhat regularly, such as cycles of high rain and low rain that occur every 5 to 10 years.

Question 22

Random disruption

Answer 22

Occurring with no regular pattern such as volcanic eruptions or hurricanes.

Question 23

Resistance

Answer 23

In an ecosystem, a measure of how much a disruption can affect flows of energy and matter.

Question 24

Resilience

Answer 24

The rate at which an ecosystem returns to its original state after a disruption.

Question 25

Intermediate disturbance hypothesis

Answer 25

The hypothesis that ecosystems experiencing intermediate levels of disturbance will favor a higher level of diversity of species than those with high or low disturbance levels.

Question 26

Evolution

Answer 26

A change in the genetic composition of a population over time.

Question 27

Microevolution

Answer 27

Evolution at the population level.

Question 28

Macroevolution

Answer 28

Evolution that gives rise to new species, genera, families, classes, or phyla.

Question 29

Evolution by artificial selection

Answer 29

The process in which humans determine which individuals to breed, typically with a preconceived set of traits in mind.

Question 30

Evolution by natural selection

Answer 30

The process in which the environment determines which individuals survive and reproduce.

Question 31

Fitness

Answer 31

An individual’s ability to survive and reproduce.

Question 32

Adaptation

Answer 32

A trait that improves an individual’s fitness.

Question 33

Evolution by random processes

Answer 33

The processes that alter the genetic composition of a population over time, but the changes are not related to differences in fitness among individuals.

Question 34

Allopatric speciation

Answer 34

The process of speciation that occurs with geographic isolation.

Question 35

Sympatric speciation

Answer 35

The evolution of one species into two, without geographic isolation.

Question 36

Genetically modified organism (GMO)

Answer 36

An organism produced by copying genes from a species with some desirable trait and inserting them into other species of plants, animals, or microbes.

Question 37

Ecological succession

Answer 37

The predictable replacement of one group of species by another group of species over time.

Question 38

Primary succession

Answer 38

Ecological succession occurring on surfaces with bare rock and no soil.

Question 39

Pioneer species

Answer 39

In primary succession, species that can survive with little to no soil.

Question 40

Secondary succession

Answer 40

The succession of plant life that occurs in areas that have been disturbed but have not lost their soil.

Question 41

Climax community

Answer 41

Historically described as the final stage of succession.

Question 42

Keystone species

Answer 42

A species that is not very abundant but has large effects on an ecological community.

Question 43

Indicator species

Answer 43

A species that demonstrates a particular characteristic of an ecosystem.

Question 44

Endemic species

Answer 44

Species that live in a very small area of the world and nowhere else, often in isolated locations such as the Hawaiian Islands.

Question 45

Biodiversity hotspots

Answer 45

Isolated areas that are home to so many endemic species, that they contain a high proportion of all the species found on Earth.