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Question 1

Genetic Variation

Answer 1

Phenotypic variation - varied expression in same population

Natural selection - select traits become more common (random mutation, non-random selection)

Question 2

Genetic drift

Answer 2

Change alone shifts phenotype

Change in alleles by chance (due to random event)

Founder effect - few individuals leave population which creates limited gene pool to start (likely carry-over recessive traits)

Question 3

Gene flow

Answer 3

New alleles enter population
New phenotype in a new generation

Transfer of alleles into or out of population

Question 4

Individual Genetic variation

Answer 4

Genetic variability - whole gene level variation

Nucleotide variability - molecular variability in DNA
(molecular variation doesn’t equal change phenotype

Non heritable variability - acquired traits cannot be passed down

Question 5

Source of genetic variation

Answer 5

New (mutant) alleles - neural variation (no observed affect)

Gene number/position - translocation of one gene (small - okay, large - bad)

Rapid reproduction - more prevalent in prokaryotes

Sexual reproduction - shuffling of alleles (crossing over, independent assortment, fertilization)

Question 6

Population and Genetics

Answer 6

All individuals in one area at one time that may interbreed and exchange genes

Evolution -genes change through genetic variation

Changes compound and new species form

Question 7

Mircoevolution

Answer 7

“small scale” evolution
Genes + Environment = expressed traits

Question 8

Hardy-Weinberg Equilibrium

Answer 8

Dominant allele - p
Recessive allele - q
Gene pool -> p+q=1.0
Allelic frequencies ->
p^2 + 2pq + q^2 = 1.0

Non-evolving population - allelic and genotypic frequencies in equilibrium, only follows Mendelian inheritance with random mating in large, sexually reproducing population

Question 9

Hardy Weinberg equilibrium is true if…

Answer 9

1) No mutations
2) No migration
3) Large gene pool
4) Random mating
5) No selection

Question 10

Genetic bottleneck

Answer 10

Small fragmented population with limited genetic diversity
(Gene pool is restricted)

Question 11

Consequences of Genetic Drift

Answer 11

1) Significant in small populations
2) Allele frequency may change at random
3) Loss of genetic variation within a population
4) Harmful alleles may become fixed

Question 12

Natural Selection

Answer 12

Random variation and non-random selection

three types - Directional, Disruptive, Stabilizing

Question 13

Absolute fitness

Answer 13

Individuals contribute to gene pool

Question 14

Relative fitness

Answer 14

Individual contribution relative to all individuals

Question 15

Genetically fit individuals

Answer 15

Most likely to contribute genes
“survival of the fittest”

Question 16

Directional Selection

Answer 16

Extreme phenotype is favored
May occur as population adapts

Question 17

Disruptive Selection

Answer 17

2+ extreme phenotypes favored
Not intermediate
Two phenotypes in same population

Question 18

Stabilizing Selection

Answer 18

Intermediate form selected
More likely to be carried over
Reduced phenotypic variability

Question 19

Sexual Selection

Answer 19

Adaptive changes to males and females
Males - higher ability to complete
Females - picky about males

(runaway, differential, dimorphism, intrasexual, intersexual)

Question 20

Runaway Selection

Answer 20

Extremely favored
Extreme may become bad

Question 21

Differential sexual selection

Answer 21

Less choosy females and most fit males
Stabilize the population

Question 22

Sexual dimorphism

Answer 22

Distinct differences between sexes
Size and color are most common differences
helps establish fitness

Question 23

Intrasexual selection

Answer 23

Individuals within sex compete with one another
Males patrol/protect territory
“psychological” competition prevents physical competition

Question 24

Intersexual selection

Answer 24

Male choice is noticeable
Chooses individuals with better genes