Bio 113: Chapter 24

Front 1

Population Genetics

Back 1

Study of genes/genotypes in a population

- extent of genetic variation

-Frequencies of alleles and genotypes

(Microevolution)

Front 2

Genetics/DNA

Back 2

Long sequences of nucleotide base pairs

-code for proteins

Front 3

hydrophilic

Back 3

Waterloving

Front 4

Hydrophobic

Back 4

Water hating

Front 5

Transcription

Back 5

DNA to RNA (In cytoplasm)

Front 6

Translation

Back 6

Cytoplasm to amino acids (Codons code for amino acids)

Front 7

DNA

Back 7

Homologous Chromosomes

-one from each parent. 2 "Copies"

Front 8

Allele

Back 8

a variant form/ version of a gene

Front 9

Genotype

Back 9

frequency, DNA sequence combination of genes

Front 10

Phenotype

Back 10

expression of the gene

-color

Front 11

Polymorphic

Back 11

Many forms of most genes

-individuals genes

-Variation 2+ alleles

Front 12

Monomorphic

Back 12

Predominantly single allele

-large, healthy populations have lots of variation

Front 13

Gene pool

Back 13

Collection of all alleles in a populaiton

Front 14

Who contributes to the next gen's gene pool?

Back 14

The parents

Front 15

Allele Frequency

Back 15

# copies of the allele of interest

_____________________________________

Total # copies of ALL alleles in the pop.

Front 16

Genotype Frequency

Back 16

# individuals w/ genotype of interest

________________________________________

Total # of ALL individuals in the pop.

Front 17

Homozygous

Back 17

Same allele

-RR

Front 18

Heterozygous

Back 18

Different copies of alleles

-Rb

Front 19

Mendelian Genetics

Back 19

-Complete Dominance

-Incomplete Dominance

-Codominance

Front 20

Complete Dominance

Back 20

dominant and recessive

Front 21

Incomplete Dominance

Back 21

Blended phenotype

Front 22

Codominance

Back 22

Both are expressed

Front 23

Hardy-Weinberg

Back 23

Relationship between allele and genotype frequence when a pop. is not evolving

Front 24

Hardy-Weinberg Assumes

Back 24

-No new mutation

-No natural selection

-Large pop. no random changes in frequencies

-No migration

-Random mating only

Front 25

Hardy-Weinberg Equation meaning

Back 25

The frequency of each allele in a pop. adds up to 1. (P+Q=1)

Front 26

Hardy-Weinberg Equation

Back 26

P^2 + 2pq + q^2 = 1

Front 27

P^2

Back 27

Frequency of genotype p/p homozygoes

Front 28

2 pq

Back 28

Frequency of p/q heterozygotes

Front 29

q^2

Back 29

Frequency of genotype q/q homozygotes

Front 30

New genetic variation

Back 30

Mutations, Gene duplication, horizontal gene transfer

Front 31

Single Nucleotide Polymorphisms (SNP)

Back 31

most common variation

Front 32

Evolutionary Mechanisms

Back 32

-Natural Selection

-Genetic drift

-migration

-nonrandom mating

Front 33

Natural Selection

Back 33

Heritable beneficial traits become more common over time

-Results in adaptations - changes in pop. that increase ability to survive and reproduce

Front 34

Reproductive Success

Back 34

likelihood of contributing fertile offspring to next gen.

Front 35

Survival

Back 35

Better adapted to environment more likely to survive to adulthood

-Natural Selection

Front 36

Reproduction

Back 36

-Directly linked to reproduction

-Better chance to find a mate

-Better production of viable gametes

"Showy Traits"

Front 37

Evolutionary Fitness

Back 37

"Survival of the fittest"

Front 38

Fitness

Back 38

Relative likelihood a genotype will contribute to gene pool of next generation

-Quantitative

Front 39

Patterns of Natural Selection

Back 39

-Directional

-Disruptive/Diversifying

-Stabilizing

-Balancing

Front 40

Directional Selection

Back 40

Whole population moves in one direction

-exp. light fur to dark fur

Front 41

Stabilizing Selection

Back 41

The intermediate is favored

-exp. few to many middle is more favored

babies

Front 42

Disruptive/Diversifying Selection

Back 42

Both Extremes are favored, Intermediate gone

exp. a wave

Front 43

Balancing Selection

Back 43

Keeps all alleles in the environment

-maintains genetic diversity

-Heterozygote advantage A/B do best

-Negative frequency-dependent selection

exp. red blood cells sickle cells

Front 44

Population of rabbits in an environment which is becoming colder and snowier over the years so dark turns to white

Back 44

Directional

Front 45

affecting the body size of males in this cichlid fish population past-similar intermediate size of all males future- man large males, many tiny males no in between

Back 45

Disruptive

Front 46

Birth weight of human babies, where intermediates are favored

Back 46

stabilizing

Front 47

Sexual Selection

Back 47

Form of natural selection

often affects male traits more

Front 48

Intrasexual selection

Back 48

compete for mates

often direct conflicts

Front 49

Intersexual Selection

Back 49

Often results in showy characteristics

cryptic female choice

Front 50

random mating

Back 50

Random selection of mates

-doesn't really happen

Front 51

Types of random mating

Back 51

-Assortative mating

-Disassortative mating

Front 52

Assortative mating

Back 52

Two likes

Front 53

Disassortative mating

Back 53

two opposites

Front 54

Inbreeding

Back 54

negative consequences with recessive alleles

Front 55

Inbreeding Depression

Back 55

Lower mean fitness if homozygous offspring have a lower fitness value

Front 56

Genetic Drift

Back 56

Changes in allele frequency due to random chance

-Large affects on small populations

Front 57

Genetic Drift scenarios

Back 57

-Bottleneck Effect

-Founder Effect

Front 58

Bottleneck Effect

Back 58

Only allows a few individuals through, different allele frequency is reflected in todays population

Front 59

Founder Effect

Back 59

a few individuals from a population start a new population with a different allele frequency than the original population

Front 60

Migration/ Gene flow

Back 60

Pop 1. has barrier in between to pop. 2 so they can interbreed