Chapter 5

Question 1

Ecosystem Diversity

Answer 1

within a region, the variety of ecosystems

Question 2

Species Diversity

Answer 2

within a given species, the variety of species

Question 3

Genetic Diversity

Answer 3

within a given species, the measure of the variety of genes

Question 4

Species Richness

Answer 4

the number if species in a given area (such as a pond, the canopy of a tree, or a plot of grassland)

Question 5

Species Evenness

Answer 5

tells us whether a particular ecosystem is numerically dominated by one species or whether all of its species have similar abundances

Question 6

Phylogenies

Answer 6

the branching patterns of evolutionary relationships

Question 7

Evolution

Answer 7

a change in the genetic composition of a population over time

Question 8

Microevolution

Answer 8

evolution below the species level, such as the evolution of different varieties of apples or potatoes

Question 9

Macroevolution

Answer 9

when genetic changes give rise to new species, or to new genera, families, classes, or phyla

Question 10

Genes

Answer 10

physical locations on chromosomes within each cell of an organism

Question 11

Genotype

Answer 11

the complete set of genes in an individual

Question 12

Mutation

Answer 12

an occasional mistake in the copying process produces a random change

Question 13

Recombination

Answer 13

occurs as chromosomes are duplicated during reproductive cell division and a piece of one chromosome breaks off and attaches to another chromosome

Question 14

Phenotype

Answer 14

the actual set of trait’s expressed in that individual

Question 15

Phenotype

Answer 15

the actual set of trait’s expressed in that individual

Question 16

Evolution by Artificial Selection

Answer 16

when humans determine which individuals breed (typically with a preconceived set of traits in mind)

Question 17

Evolution by Natural Selection

Answer 17

the environment determines which individuals survive and reproduce

Question 18

Fitness

Answer 18

an individual’s ability to survive and reproduce

Question 19

Adaptations

Answer 19

traits that improve an individual’s fitness

Question 20

Genetic Drift

Answer 20

a change in the genetic composition of a population over time as a result of random mating

Question 21

Bottleneck Effect

Answer 21

a reduction in the genetic diversity of a population caused by a reduction in its size

Question 22

Founder Effect

Answer 22

a change in a population descended from a small number of colonizing individuals

Question 23

Geographic Isolation

Answer 23

a subset of individuals from a larger population may colonize a new area of habitat that is physically separated from that of the rest of the population

Question 24

Geographic Isolation

Answer 24

a subset of individuals from a larger population may colonize a new area of habitat that is physically separated from that of the rest of the population

Question 25

Reproductive Isolation

Answer 25

species can no longer interbreed and produce viable offspring

Question 26

Allopatric Speciation

Answer 26

requires geographic isolation

Question 27

Sympatric Speciation

Answer 27

the evolution of one species into two species in the absence of geo-graphic isolation

Question 28

Genetically Modified Organisms

Answer 28

have genes from other species of plants, animals, or microbes inserted by scientists

Question 29

Range of Tolerance

Answer 29

limits to the abiotic conditions a species can tolerate, such as extremes of temperature, humidity, salinity, and pH

Question 30

Fundamental Niche

Answer 30

the suite of ideal conditions for a species

Question 31

Realized Niche

Answer 31

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

Question 32

Distribution

Answer 32

the areas of the world in which a species lives

Question 33

Niche Generalists

Answer 33

organisms that can live in a variety of habitats or feed on a variety of species

Question 34

Niche Specialists

Answer 34

Organisms specialized to live in a specific habitat or feed on a small group of species

Question 35

Fossils

Answer 35

the remains of organisms that have been preserved in rock

Question 36

Mass Extinction

Answer 36

large numbers of species went extinct over relatively short periods of time