Chap 19, 20 22

Question 1

Evolution

Answer 1

descent with modification. Change in the genetics of a pop from one generation to the next.

Question 2

natural selection

Answer 2

individuals inherit traits that make them more likely to survive and reproduce

Question 3

artificial selection

Answer 3

Human modifications of traits through breeding.

Question 4

homologous structures

Answer 4

variations on a structural theme that was present in a common ancestor.

Question 5

Vestigial structures

Answer 5

remnants of features that served a function in the organism’s ancestors

Question 6

Analogous structures

Answer 6

species that share similar features because of convergent evolution but don’t share ancestors.

Question 7

Common descent

Answer 7

one species is the ancestor of two or more species later in time.

Question 8

Convergent evolution

Answer 8

evolution of similar features through different lineages

Question 9

microevolution

Answer 9

change in the allele frequencies in a population over generations

Question 10

Five conditions for Hardy Weinberg

Answer 10

no Mutations, Random mating, No nat selection, large pop, no gene flow

Question 11

founder effect

Answer 11

occurs when a few indiv get isolated from general pop and form a new population

Question 12

Bottleneck effect

Answer 12

happens when size of pop is reduced

Question 13

Directional selection

Answer 13

occurs when conditions favor indiv exhibiting one characteristic-shifts the pops frequency

Question 14

Disruptive selection

Answer 14

occurs when conditions favor indiv at both extremes of a range

Question 15

Stabilizing selection

Answer 15

acts against both extremes and favors the intermediate variations

Question 16

heterozygote advantage

Answer 16

greater reproductive success of heterozygous indivi.

Question 17

sexual dimorphism

Answer 17

difference in secondary sexual characteristics of males and females of the same species.

Question 18

reproductive isolation

Answer 18

biological factors that prevent members of 2 species from breeding and producing fertile offspring

Question 19

Prezygotic

Answer 19

prevents fertilization from occuring

Question 20

postzygotic

Answer 20

a mechanism that blocks reproduction after fertilization and zygote formation.

Question 21

autopolyploid chromosome change

Answer 21

doubles a cells chromosome #

Question 22

Allopolyploid chromosome change

Answer 22

changes a sterile hybrid to a fertile