Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Bio 1010 > Evolution > Flashcards

Evolution Flashcards

Hardy-Weinberg, Evolution, Mutation

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

In the Hardy-Weinberg equation, what does each variable represent?

A 
p = frequency of dominant allele
q = frequency of recessive allele
p^2 = frequency of homozygous dominant individuals
q^2 = frequency of homozygous recessive individuals
2pq = frequency of heterozygous individuals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the Hardy-Weinberg equation?

A

Method of determining genotype frequencies from allele frequencies. A mathematical representation of a gene pool. Assumes the population is in genetic equilibrium.
p^2 + 2pq + q^2
(should add to 1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How do you calculate allele frequencies from genotype frequencies?

A 
p = RR + 1/2 Rr
q = rr + 1/2 Rr
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the three requirements for natural selection?

A
  1. There is heritable variation
  2. There is a struggle for existence
  3. The heritable variation influences the struggle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the Hardy-Weinberg equation assume?

A
  • No Mutations
  • No Gene Flow
  • Random Mating
  • No Genetic Drift
  • No Selection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is Microevolution?

A

An accumulation of small changes in a group or species. A change in the gene pool of a population over time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a population?

A

A group of individuals of the same species living together in the same area at the same time.
-Smallest biological unit that can evolve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When is a population said to be Polymorphic for a characteristic?

A

When two or more morphs or forms are present in noticeable numbers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do mutation and sexual recombination produce new genetic variation?

A

Mutation creates new variation. Ultimate source of variation.

Meiosis reshuffles the existing variation. Contributes the most to genetic variation between individuals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the causes of microevolution?

A
  • Mutations
  • Gene Flow
  • Non-random Mating
  • Genetic Drift
  • Natural selection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is assortative mating?

A

Individuals tend to mate with those with the same phenotype, results in more homozygotes than expected.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is disassortative mating?

A

Individuals tend to mate with those with a different phenotype, resulting in more heterozygotes than expected.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is sexual selection?

A

Males fight for the right to reproduce and females choose males with a particular phenotype.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is inbreeding?

A

The most common form of non-random mating.

Individuals tend to mate with genetic relatives, resulting in more homozygotes than expected.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is genetic drift?

A

Changes in the allele frequency of a population due to random chance. Has a larger effect on smaller populations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the bottleneck effect?

A

Happens when an event causes a drastic reduction in population size, preventing the majority of genotypes from entering the next generation. This results in a loss of genetic variability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the founder effect?

A

One or a few individuals disperse and form a new population. Some alleles are lost and others change in frequency.

18
Q

What is disruptive selection?

A

Selection that favors the two extremes, and acts to eliminate intermediate types. M

19
Q

What is directional selection?

A

An extreme phenotype is favored and the distribution curve shifts in that direction. Acts to eliminate one extreme.

20
Q

What is stabilizing selection?

A

Occurs when an intermediate phenotype is favored. Acts to eliminate both extremes.

21
Q

What is heterozygote advantage?

A

Heterozygotes are favored over homozygotes.

Works to maintain both alleles in the population.

22
Q

What is frequency-dependent selection?

A

When the fitness of a phenotype depends on how frequently or infrequently a phenotype occurs in a population.

23
Q

What is negative frequency-dependent selection?

A

When rare phenotypes are favored by selection.

- Maintains variation in the population.

24
Q

What is positive frequency-dependent selection?

A

When common phenotypes are favored by selection.

- Eliminates variation from the population.

25
Q

What is oscillating selection?

A

When selection favors one phenotype at one time and another phenotype at another time.
- Maintains variation in the population

26
Q

What is pleiotropy?

A

When one gene has multiple phenotypic effects.

27
Q

What is epistasis?

A

Interaction between genes.

28
Q

What is speciation?

A

The splitting of one species into two or more species, or the transformation of one species into a new species over time.

29
Q

What is macroevolution?

A

Large scale evolutionary change, usually over long periods of time, leading to new species and new lineages.

30
Q

What is the morphological species definition?

A

Based on morphological differences, the classic way to define separate species.

31
Q

What is the biological species definition?

A

Uses population genetics based on reproductive isolation. Separate species have separate gene pools, there is no gene flow between them.

Cannot be applied to asexual or extinct species.

32
Q

What is behavioral isolation?

A

Sympatric species avoid mating with members of the wrong species in a variety of ways, including differences in pheromones, visual signals, sounds,and electrical signals.

33
Q

What is mechanical isolation?

A

Reproductive isolation based on the fact that genitalia don’t match; position of pollen and stigma in flower don’t match; attract different pollinators.

34
Q

What is temporal isolation?

A

Reproductive isolation based on mating at different times.

35
Q

What is cladogenesis?

A

When one ancestral species becomes divided into two descendant species.

36
Q

What is the phylogenetic species definition?

A

Uses biochemical genetics and compares DNA to indicate relatedness of groups of organisms.

37
Q

What is allopatric speciation?

A

Given time, any two isolated populations will diverge because of genetic drift. Speciation that occurs in different locations.

38
Q

What is sympatric speciation?

A

Speciation that occurs in the same location.

39
Q

What is adaptive radiation?

A

When many new closely species evolve from a common ancestor when members of the species become adapted to different environments.

40
Q

What is phyletic gradualism?

A

The accumulation of small changes over long time periods.

41
Q

What is punctuated equilibrium?

A

Long periods of stasis followed by rapid change.

Bio 1010 (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions