Ch thirteen evolution test X_X

Question 1

Biogeography

Answer 1

• geographic distribution of species
• migration from one place to another
• new species form but resemble old species in other locations

Question 2

comparative anatomy

Answer 2

• anatomical similarities between species

Question 3

homology

Answer 3

similar characteristics that result from common ancestry

Question 4

homologous sructures

Answer 4

features that have different functions but similar structures

Question 5

vestigial structures

Answer 5

leftover features that used to serve an important function in the orgnism’s ancestors

Question 6

analagous structures

Answer 6

same function, different strucures

Question 7

comparative embryology

Answer 7

comparisons of the early stages of development of two different species

Question 8

molecular biology

Answer 8

homologous genes with similar sequences

Question 9

artificial seletion

Answer 9

shaping evolution by human intervention

Question 10

evolution is apparent when…

Answer 10

seen in a population

Question 11

population

Answer 11

a group of individual organisms from the same species that live in the same area and interbreed

Question 12

gene pool

Answer 12

total collection of genes in a population at any one time… alll the alleles

Question 13

mutations

Answer 13

• a change of the normal nucleotide sequence of DNA
• usually not great for the organism
• very rarely a mutant allele might improve the genome
  -differentiation of small pieces of DNA could lead to new genes with novel functions

Question 14

Sexual reproduction

Answer 14

most genetic variation occurs from the combination of alleles in offspring

Question 15

Three components of sexual reproduction

Answer 15

• crossing over– prophase one, meiosis
  -independent assortment
  -random fertilizaton

Question 16

• Five requirements for Hardy Weinberg to be true

Answer 16

• very large population
  -no gene flow between populations
• no mutations
  -random mating
  -no natural selection

Question 17

Microevolution

Answer 17

• random/ rare events
• three main methods
  -bottleneck effect
  -founder effect
  -gene flow

Question 18

Bottleneck effect

Answer 18

• drastic population reduction
• natural disasters
• genetic drift may continue for many generations until the population builds back up

Question 19

founder effect

Answer 19

• genetic drift that occurs when a small set of individuals found a new habitat

Question 20

Gene flow

Answer 20

immigration/ emigration

Question 21

polymorphic

Answer 21

a population where there are more than two forms of a characteristic

Question 22

balancing selection

Answer 22

occurs when natural selection maintains stable frequencies of two or more phenotypes

Question 23

heterozygote advantage

Answer 23

possible explanation for balanced polymorphism

Question 24

frequency dpendant selection

Answer 24

the survival and reproduction of any one form declines if phenotype becomes too common

Question 25

directional selection

Answer 25

graph with arc shifted either to the right or left

shift in the genetic makeup of population by favoring one phenotype to the extreme

Question 26

stabilizing selection

Answer 26

one arc higher than original

favors an intermediate trait

Question 27

disruptive selection

Answer 27

MacDonalds M on drugs graph

favors both ends of a phenotypic range

Question 28

sexual selection

Answer 28

form of natural selection in which animals with certain traits have a higher chance of finding a mate

Question 29

sexual dimorphism

Answer 29

distinction in appearance

Question 30

intrasexual selection

Answer 30

individuals of one sex choose their mate

Question 31

Four reasons why natural selection cannot make a perfect organism

Answer 31

• selection can only go on existing variations
• evolution is limited by historical constraints
• adaptations are often compromises
• change natural selection, environment changes