third quiz

Question 1

what are the two types of evolutionary genetics ?

Answer 1

population genetics

quantitative genetics

Question 2

what is population genetics

Answer 2

study of the fate of alleles at one or more loci

p and q stuff

Question 3

what is quantitave genetics

Answer 3

study of traits assumed to be controlled by many loci

Question 4

is height in humans population genetics or quantitative genetics

Answer 4

quantitative

Question 5

what are the different ways alleles at a loci affect phenitypes

Answer 5

dominance
epistasis
pleiotropy
plasticity

Question 6

what is dominance

Answer 6

interactions between alleles at a loci

normal recessive/dominance stuff

Question 7

what is epistasis

Answer 7

interactions across loci

effect of a gene mutation is dependant on the presence of absence of a mutation on one or more genes

Question 8

what is pleiotropy

Answer 8

interactions across traits

when one gene influences multiple seemingly unrelated phenotypic traits

Question 9

what is plasticity

Answer 9

interactions with environment

change in the expressed phenotype of a genotype as a result of the environment

Question 10

what is codominance

Answer 10

both alleles in the genotype are seen in the the phenotype

Question 11

what is incomplete dominance

Answer 11

when the phenotypes of the parents blend together to create a new phenotype

Question 12

what does the hardy Weinberg equation describe

Answer 12

the unchanging frequency of alleles in a stable, idealized population

Question 13

what does hardy Weinberg assume

Answer 13

large populations, no selection, no migration, random mating, no mutation

Question 14

in hardy Weinberg equilibrium do allele frequencies change over time

Answer 14

no

Question 15

what are the classes of selection

Answer 15

viability selection

fecundity selection

Question 16

what is viability selection

Answer 16

differences in survival probabilities

Question 17

what is fecundity selection

Answer 17

differences in reproductive success

Question 18

how do new dominant mutations affect frequency and fixation

Answer 18

increase in frequency rapidly

approaches fixation slowly

Question 19

how do new recessive mutations affect frequency and fixation

Answer 19

increase frequency very slowly

once they are common they reach fixation very quickly

Question 20

Are most new mutations recessive or dominant

Answer 20

most are at least partially recessive

Question 21

what are ways genetic variation is maintained

Answer 21

• recessive alleles linger even if selected against
• directly via selection (ex:heterozygote advantage, frequency-dependant selection, mosaic evolution that counteracts migration)
• via recurrent mutation
• via drift

Question 22

what is a heterozygote advantage

Answer 22

when the heterozygote has a higher fitness than the homozygote

Question 23

what is frequency dependant selection

Answer 23

each selection coefficient is a function the frequencies of the different genotypes.
pretty much frequency of the genotypes influences likelihood of getting that genotype

Question 24

what is mosaic evolution

Answer 24

different geographic locations lead to different fitnesses for the same allele

Question 25

what is mutation selection balance

Answer 25

new copies of alleles keep arising by mutation making it so it persists at a low frequency

Question 26

what are Darwins 2 big ideas

Answer 26

natural selection | decent with modification

Question 27

what is homology

Answer 27

similarities due to a common ancestor

Question 28

what is analogy

Answer 28

similarities due to convergent evolution

Question 29

what is apomorphy

Answer 29

when a species/clade shows a trait that identifies it from the ancestral form

Question 30

symplesiomorphy

Answer 30

a characteristic shared by 2 or more taxa and their most recent common ancestor

Question 31

what is plesiomorphy

Answer 31

ancestral trait

Question 32

what is autapomorphy

Answer 32

a distinctive feature (derived trait) that is unique to a taxon (only found in one taxon)

Question 33

what is a synapomorphy

Answer 33

characteristic shared by a group of taxa due to common ancestor

Question 34

what is homoplasy

Answer 34

a characteristic shared by a set of species but not their common ancestor

Question 35

what are the three parts of a phylogenetic tree

Answer 35

tips, nodes, branches

Question 36

what is each branch and node represent

Answer 36

a phylogenetic species

Question 37

what is a root

Answer 37

a common ancestor of all taxa in the tree

Question 38

what is a sister group

Answer 38

closest living species relative to another

Question 39

what do rooted trees incorporate

Answer 39

relative time

Question 40

what is an outgroup

Answer 40

taxon outside of group of interest (ingroup)

Question 41

what do cladograms represent

Answer 41

relative relationships

Question 42

what do additive trees show

Answer 42

branch lengths represent the amount of change and isn't indicative of the amount of time

Question 43

what do ultrametric trees show

Answer 43

branch lengths show relative time | all living species are same distance from the root

Question 44

order types of trees from least complex (amount of information shown) to most

Answer 44

unrooted trees cladogram additive tree ultranetric tree

Question 45

what is polytomy

Answer 45

a node on a phylogeny with more than 2 decendant lineages emerging

Question 46

what does it mean to be bifurcating (dichotomous)

Answer 46

to divide into 2 branches

Question 47

what is a monophyletic group (clade)

Answer 47

consists of a node and all of its descendants

Question 48

what is a paraphyletic group

Answer 48

contains a node and some but not all descendants

Question 49

what is a polyphyletic group

Answer 49

when two lineages convergently evolve similar character states