Mcat Biology Evolution

Front 1

differential reproduction

Back 1

individuals with more favorable gene produce more offspriing

Front 2

puncuated equilibrium

Back 2

1. short period of evo with long periods of stasis
2. evolution occurs in spurts

Front 3

Genetic drift

Back 3

changes in the composition of a gene pool due to change

Front 4

Gene flow

Back 4

net gain or loss of a gene pool due to migration

Front 5

Prezygotic isolation mechanism

Back 5

1. temporal isolation
2. ecological isolation
3. behavorial isolation
4. reproductive isolation
5. gametic isolation

Front 6

Postzygotic isolation

Back 6

1. hybrid inviability
2. hybrid sterility
3. hyrid breakdown

Front 7

adaptive radiation

Back 7

1. emergence of a number of lineages from a single ancestral species
2. differences btwn species are those adaptive to a distinct lifestyle or niche

Front 8

convergent evolution

Back 8

indpendent development of similar characteristics into 2 or greater lineages not sharing a recent common ancestor

Front 9

divergent evolution

Back 9

independent development of dissimilar characteristics in two or more lineages sharing a common ancestry

Front 10

parallel evolution

Back 10

process whereby related species eveolve in similar ways for a long period of time in response to analogous environmental selection presssures.

Front 11

Directional selection

Back 11

bell curve, follows natural selection

Front 12

Divergent selection

Back 12

bell curve goes to the extremes (less "average"), extremes form a new species

Front 13

stabilizing selection

Back 13

extremes are selected against

Front 14

artificial selection

Back 14

humans control mating

Front 15

sexual selection

Back 15

mating is not random

Front 16

kin selection

Back 16

animals that live socially can pass on alleles

Front 17

anagenesis

Back 17

can't reproduce with ancestors

Front 18

cladogenesis

Back 18

one species becomes two or more species

Front 19

allopatric isolation

Back 19

geographic isolation

Front 20

sympatric isolation

Back 20

species give rise to new species in same geographic area

Front 21

homologous structures

Back 21

common structures due to ancestry

Front 22

analogous structures

Back 22

common structures not due to ancestry

Front 23

Five assumptions of the Hardy-Weinberg equation

Back 23

1. no mutation
2. no natural selection
3. random mating
4. no migration
5. large population

Front 24

If conditions for HWE are met, how long does it take a population to meet HW equilibrium?

Back 24

One generation

Front 25

fitness

Back 25

how well (sucessful) an organism is on passing its alleles onward, more offspring

Front 26

t/f
NS works on both phenotypes and geneotypes

Back 26

f
NS only works on phenotypes

Front 27

t/f
NS can only alter alleles, not creat new alleles

Back 27

t

Front 28

Two sources of genetic variation

Back 28

new alleles (from mutation) & combos of existing alleles

Front 29

temporal isolation

Back 29

two species may breed during different seasons or different time of the day.

Front 30

ecological isolation

Back 30

two species living in the same territory but not the same habitat

Front 31

behavorial isolation

Back 31

not sexually attracted to eachother due to phermones

Front 32

reproductive isolation

Back 32

genitalia of two species are incompatible, so interbreeding cannot occur

Front 33

gametic isolation

Back 33

intercourse can occur, but fertilization cannot.

Front 34

hyrbid inviability

Back 34

genetic incompatibilities

Front 35

hybrid sterility

Back 35

hybrid offspring sterile

Front 36

hybrid breakdown

Back 36

first-generation hybrids are viable and fertile, but 2nd generation hybrid offspring are inviable and/or infertile