Unit Two: Evolution

Question 2

What are the three kinds of mutations?

Answer 2

Substitution, Insertions, Deletion

Question 3

What is substitution?

Answer 3

The replacement of one base nucleotide with another in DNA

Question 4

What is insertion?

Answer 4

The addition of one or more bases in DNA sequences

Question 5

What is deletion?

Answer 5

The removal of one or more bases in DNA sequences

Question 6

What is a beneficial mutation?

Answer 6

A change that has an advantage in survival or reproduction, increasing their ability to pass on genetic material

Question 7

What is a neutral mutation?

Answer 7

A change does not create an advantage or disadvantage for reproductive success or survival

Question 8

What is a harmful mutation?

Answer 8

A change that creates a disadvantage for survival or reproductive success

Question 9

What is natural selection?

Answer 9

The process by which organisms with traits that increase fitness are more likely to pass these traits to the next generation

Question 10

What is fitness?

Answer 10

An individuals ability to survive and reproduce

Question 11

What is allele frequency?

Answer 11

The proportion of individuals in a population carrying the same allele

Question 12

What is Stabilizing selection?

Answer 12

Natural selection where moderate traits are favored and extremes are selected against

Question 13

What is directional selection?

Answer 13

Natural selection where an extreme is being selected for and the opposite extreme and moderate are selected against

Question 14

What is disruptive selection?

Answer 14

Natural selection where both the extremes are favored for and the mean is selected against

Question 15

What are selection pressures?

Answer 15

Environmental factors that define whether an organism will be more or less successful at surviving and reproducing

Question 16

What are the three kinds of selection pressures?

Answer 16

Resource availability, environmental factors, biological factors

Question 17

What is sexual selection?

Answer 17

The selection of traits from the preference one sex has for certain characteristics in individuals of the other sex

Question 18

What are sexual dimorphisms?

Answer 18

Distinct differences in size, shape, color, or other physical characteristics between males and females of the same species

Question 19

What is genetic drift?

Answer 19

The change in allele frequency over generations due to random chance (bottleneck and founder effects)

Question 20

What is gene flow?

Answer 20

Transfer of alleles and genes between different populations of the same species through migration and reproduction, contributing to genetic diversity

Question 21

What is artificial selection?

Answer 21

Intentional breeding of organisms by humans to promote specific desirable traits or characteristics that have benefit to humans

Question 22

What is the Hardy-Weinberg equilibrium?

Answer 22

An equation that describes the allele frequencies in a population under ideal conditions when no evolution is occurring

Question 23

What is the equation for allele frequencies?

Answer 23

P+Q=1

Question 24

What is the equation for genotype frequencies?

Answer 24

P2+2PQ+Q2=1

Question 25

What is genetic diversity?

Answer 25

The variety of alleles within a population of a species

Question 26

Define biological evolution

Answer 26

All species on earth today are descended from ancestral species which have adapted over time

Question 27

Define species

Answer 27

A group of organisms that can be interbred, produce fertile offspring, share common characteristics

Question 28

What is speciation?

Answer 28

When populations become reproductivily isolated and diverge, creating new species

Question 29

What is a reproductive isolating mechanism?

Answer 29

Anything that prevents successful reproduction from occurring

Question 30

What is micro evolution?

Answer 30

Small scale changes that occur within a population over a relatively short period of time

Question 31

What is macro evolution?

Answer 31

Large scale changes that occur over long periods of time and result in the formation of new species

Question 32

What is divergent evolution?

Answer 32

When closely related species evolve to become different, due to different environmental pressures

Question 33

What is convergent evolution?

Answer 33

When unrelated species develop similar traits independently, due to similar environmental pressures

Question 34

What is parallel evolution?

Answer 34

When related species evolve in similar ways after diverging from a common ancestor, due to similar environmental pressures

Question 35

What is co evolution?

Answer 35

When changes in one species drives change in another species

Question 36

What is gradualism?

Answer 36

When evolution occurs through a slow and continuous accumulation of small changes over long periods of time

Question 37

What is punctuated equilibrium?

Answer 37

Species often remain relatively stable for long periods of time with rare and rapid bursts of change

Question 38

What are homologous features?

Answer 38

Traits or characteristics are similar in different species because they share a common evolutionary ancestry

Question 39

What are vestigial structures?

Answer 39

Features that have reduced in size or function because it is longer necessary for the organisms survival

Question 40

What are analogous features?

Answer 40

Features in different species that serve similar functions, but they evolved independently

Question 41

What are the five assumptions that the Hardy-Weinberg equilibrium is based on?

Answer 41

1. Large population 2. No migration 3. No mutation 4. Random mating 5. No selection