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51 Cards in this Set

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  • Back
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What 5 events create variation in gametes?
1. Mutation
2. Cross over
3. Random Alignement
4. Fertilization
5. Number of chromosomes
What 4 rules need to be followed if the Hardy-Weinberg Equilibrium is true?
1. There are no mutations
2. The population is large and isolated
3. All mating is random
4. All individuals must mate
Morphological Divergence

EG Forearm
Term and example
Change in DNA sequence having either a good, bad or no effect.
Parapatric Speciation
Neighboring populations become distinct species while continuing to maintain contact along a common barrier.
Polyploidy Speciation
Where plant offspring have a changed number of chromosomes, and inherit 3+ chromosomes of each type.
Evolution of a new species from an existing species.
One kind of organism.
Stabilizing Curve
Favors the average.

EG Birthweight
Definition and example
Stabilizing Selection
Selects for intermediaries (or heterozygotes if we are considering a single gene).

Stabilizing Curve: favors the average
EG Birthweight

also includes:
Normal Distribution: EG Height
What does it favor?
State the genotype
Give example
Geographically distinct populations of the same species.
Sympatric Speciation
New species can form within the same geographic region in the absence of a physical barrier.
This is required for speciation to take place?
Genetic isolation
What are 3 postmating (postzygotic) isolation mechanisms?
1. Hybrid inviability (kw F1 dies )
2. Hybrid sterility (kw F1 infertile)
3. Hybrid breakdown (kw F2 infertile)
3 terms and their keywords (kw)
What are 3 ways genetic drift can occur?
Founder Effect
What are 4 types of Premating (Prezygotic) Isolation?
1. Temporal Isolating Mechanism (kw timing of reproduction cycle)
2. Behavioral (kw style)
3. Mechanical (kw parts)
4. Gametic (kw chemicals)
What is the Hardy-Weinberg Equilibrium formula and what is it used for?
p = freq of homozygous dom allele
q = freq of homozygous rec allele
pq = freq of heterozygous dom allele
Converts to a genotypic ratio.

It's used to describe a population at genetic equilibrium where evolution has not occurred.
What does p, q and pq stand for?
Which is most common:
Allopatric speciation or
Sympatric speciation?
Allopatric Speciation
Allopatric or Sympatric?
_____ is to morphological divergence as _____ is to morphological convergence.
Homology : Divergence eg forearm
Analogy : Convergence eg wing of insect and bird
6 Kingdoms of Organisms
1. Eukbacteria - Prokaryotic
2. Archebacteria - Prokaryotic
3. Protista - Eukaryotic
4. Fungi - Eukaryotic
5. Plantae - Eukaryotic
6. Animalia - Eukaryotic
List and label either Pro/Eukaryotic
Modification that increases the survival of a population in a given environment.
Allopatric Speciation
Some type of physical barrier that arises and prevents gene flow between populations of species.
Structures that do not have a common evolutionary background, even though they may be morphologically similar.

EG Wing of a bird and a wing of an insect
Definition and example
Aristotle (380-320 BC)
Continuum of organisms; from lowest to highest forms.
Artificial Selection
Where we determine what's being selected.

EG Breeding purebreed cats
Definition and example
Fluctuations in the environment may cause a population to periodically experience a rapid decrease in their number, with only a few individuals from a large population surviving.
Causes of Genetic Drift
1. Inbreeding
2. Bottlenecks
3. Founder Effect
3 causes
Comparative Morphology
Change in body form of a common ancestor.
Directional Selection
Favors extremes.
Homozygous Dominant or Recessive

EG Peppered Moth
What does it favor?
State the genotype
Give example
Disruptive Selection
Favors extremes simultaneously.
Homozygous Dominant or Recessive

EG Finches beaks, large and small with none in the middle
What does it favor?
State the genotype
Give example
Irrecoverable loss of a species.
Some recognizable, physical evidence of an organism that lived in the distinct past.
Founder Effect
A few individuals from a large population establish, or found, a new population that have alleles only from the founders.
Gene Flow
Alleles enter and leave a population as a result of immigration (in) and emigration (out).
Gene Pool
All the alleles of all genes in a population at a given time.
Genetic Drift
Change in allele frequencies over generations (usually to a small population) due to CHANCE.
Genetic Mutation
Change in DNA sequence of nucleotides in a gene.
All the genes of an individual organism.
Genotype is to _______ as Gene Pool is to _______.
Individual; population
A similarity in one or more body parts in different organisms that can be attributed to descent from a common ancestor.

EG Forearm
Definition and example
How far does the earliest living organism date back?
3.5 billion years ago
How old is the earth?
4.6 billion years old
How old is the universe?
12 billion years old
Non-random mating among closely related relatives.

A way in which genetic drift occurs
Lamark (1744-1829)
"New traits could be created over a lifetime."
This person explained how one species develops from another. (We now believe that changes occur over generations not within a lifetime).
Linnaeus (1707-1829)
Creator of taxonomy.
Large scale patterns, trends, and rates of change among higher taxa (above the level of species).
Mass Extinction
Large catastrophic event in which the entire families (taxa group) disappear during the same phase at the same point in geological time.
Genetic change of a population that results from:
1. Mutation
2. Genetic Drift
3. Gene Flow
4. Natural Selection
List 4 causes
Any change in allele frequency of a population resulting form mutation, genetic drift, gene flow, natural selection, or some combination of these.
Morphological Convergence

EG The wing of a bird and the wing of an insect
Term and example