ch.14

Question 1

populations that normally interbreed and produce fertile offspring

Answer 1

biological species concept

Question 2

emergence of a new species from a previously existing species

Answer 2

speciation

Question 3

Reproductive isolation can be caused by pre-zygotic and post-zygotic barriers

Answer 3

reproductive barriers

Question 4

The human arm and whale flipper are homologous structures, meaning that

Answer 4

they are modified versions of a common ancestral structure

Question 5

Homologous structures provide evidence for evolution because

Answer 5

they are best explained by descent from a common ancestral structure

Question 6

a prediction made by Darwin that was proven.

Answer 6

that all life would depend on DNA and a common genetic code

Question 7

A hypothetical population of rodents lives on a rocky beach and have a fur colors that range from white to dark gray. A group of these rodents migrates to a forested area and after several generations only rodents with darker fur are present. This is an example of

Answer 7

directional selection

Question 8

The allele for cystic fibrosis causes a serious disease when present in two copies, but this harmful allele has not been eliminated from populations where it’s present. How do harmful alleles remain in populations?

Answer 8

harmful recessive alleys can “hide” in the diploid genomes of eukaryotes

Question 9

Natural selection can best be summarized as

Answer 9

differential reproductive success based on inherited characteristics

Question 10

Humans share features with salamanders. Some genes and proteins are nearly identical between the two species; both species have four limbs and a similar skeletal plan; the early embryos of both species are very similar; and where the salamander has a functional tail, humans have a vestigial tailbone. In evolutionary terms, these are examples of

Answer 10

homolgy

Question 11

One of the core themes of biology that we study, which explains both the unity and diversity of life, is

Answer 11

evolution

Question 12

Evolution occurs when

Answer 12

a populations allele frequencies change over a span of generations

Question 13

All new alleles and all genetic diversity ultimately derive from

Answer 13

mutation

Question 14

What do we call changes in allele frequency that result from a disaster or other event that drastically reduces population size?

Answer 14

bottleneck effect

Question 15

Of the several mechanisms that can drive evolution, which can lead to a population that is better adapted to its environment?

Answer 15

natural selection

Question 16

One of Darwin’s key observations was that geographical proximity, not environment, was the best predictor of relatedness. An example of this was the fact that many of the species on the Galápagos islands

Answer 16

were identical to South American species

Question 17

Which of the following is an example of intrasexual selection?

Answer 17

large antlers in male elk, which are used for battles between males

Question 18

Evolution explains the ____ and the _____ of life

Answer 18

unity, diversity

Question 19

Allopatric speciation

Answer 19

new species arise because of geographic separation

Question 20

prezygotic barriers & postzygotic barriers

Answer 20

pre: before zygote is formed, behavioral isolation, gametic isolation
post: reduces viability or reproductive capacity of hybrid offspring

Question 21

hybrid polyploidy

Answer 21

hybridization of two different plant species
Asexual reproduction
mostly happens in plants