Chapter 5

Question 1

The mechanism of evolution proposed by Charles Darwin in the origin of species is

Answer 1

natural selection

Question 2

The fitness of an individual is measured by

Answer 2

the proportion contribution it makes to future generations

Question 3

_________ are the specific traits of a particular organism enabling it to survive, grow ,and reproduce within a given environment

Answer 3

adaptations

Question 4

A gene is

Answer 4

a stretch of DNA coding for a polypeptide chain( sequence of amino acids)

Question 5

An allele that completely masks the effect of another allele is considered

Answer 5

dominant

Question 6

Traits that have a continuous distribution are known as

Answer 6

quantitative traits

Question 7

The gen pool refers to all the genetic information within a

Answer 7

population

Question 8

The expression of different phenotypic traits for a given genotype under different environmental conditions is referred to as

Answer 8

phenotypic plasticity

Question 9

If a population has an allele frequency of 1.0 you would say that

Answer 9

genetic variation of that allele is low

Question 10

What is an example of acclimation

Answer 10

Marine lionfish are able to tolerate freshwater estuaries

Question 11

If birds with larger beaks are favored by the environment, it is likely that ________ selection will occur

Answer 11

directional

Question 12

Measurements of bill length in a population of seed-eating birds reveal’s two distinct groups: small- billed individual feeding on soft-shelled seeds and large-billed individuals feeding on hard-shelled seeds. this bimodal distribution mostly likely resulted from

Answer 12

disruptive selection

Question 13

What is the primary original source of genetic variation in a population

Answer 13

mutation

Question 14

Under which of the following conditions would genetic drift exert the greatest influence

Answer 14

a very small population

Question 15

The movement of genes between populations is referred to as

Answer 15

gene flow

Question 16

A gradual change in phenotype across an environmental gradient, such as white-tailed deer changing gradually in size from large in the north to small in the south, is referred to as

Answer 16

a cline

Question 17

Geographic isolates of a particular species that differ from other population by one or more characteristics are considered to be

Answer 17

subspecies

Question 18

Individual beak size of individual finches of the Galapagos Islands

Answer 18

will greatly influence individual survival

Question 19

The Galapagos Islands are inhabited by 13 species of Darwin’s finches that evolved from a single species. this is an example of

Answer 19

adaptive radiation

Question 20

Natural selection is visible at the level of

Answer 20

populations