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Biology Raven 9th Edition Chapters 20, 21, 23 and 26

Biology Raven 9th Edition Chapters 20, 21, 23 and 26 (Not Finished, but pieces from all chapters are present) For 1st Exam Biology 1082
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Synapomorphy
In systematics, a derived character that is shared by clade members.
Parsimony
Principle stating that scientists should favor the hypothesis that requires the fewest assumptions.
Linnaeus
Scientist who came up with method of naming organisms with a 2 part scientific name called binomial nomenclature. Father of taxonomy
Monophyletic
All members have a single common ancestor
Polyphyletic
grouping of several species that lack a common ancestor
homologous structures
having the same evolutionary origin but serving different functions
Analogous
corresponding in function but not in evolutionary origin
Vestigial
referring to a functionless structure that was functional in an ancestral species
taxonomy
the scientific study of how living things are classified
evolution
Genetic change in a population of organisms; in general, evolution leads to progressive change from simple to complex.
Natural Selection
The principle that, among the range of inherited trait variations, those that lead to increased reproduction and survival will most likely be passed on to succeeding generations
Artificial Selection
The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits.
Genetic Variation
the number and frequency of alleles that are present in a particular population
Polymorphic
The presence in a population of more than one allele of a gene at a frequency greater than that of newly arising mutations.
Hardy-Weinberg principle
No mutation takes place.

No genes are transferred to or from other sources (no immigration or emigration takes place).

Random mating is occurring.

The population size is very large.

No selection occurs.
Hardy-Weinberg equilibrium
A mathematical description of the fact that allele and genotype frequencies remain constant in a random-mating population in the absence of inbreeding
Gene flow
movement of alleles from one population to another
assortative mating
A type of nonrandom mating in which phenotypically similar individuals mate more frequently.
disassortative mating
A type of nonrandom mating in which phenotypically different individuals mate more frequently.
Genetic Drift
Random fluctuation in allele frequencies over time by chance.
founder effect
The effect by which rare alleles and combinations of alleles may be enhanced in new populations.
bottleneck effect
A loss of genetic variability that occurs when a population is reduced drastically in size.
selection
The process by which some organisms leave more offspring than competing ones, and their genetic traits tend to appear in greater proportions among members of succeeding generations
convergent evolution
The independent development of similar structures in organisms that are not directly related; often found in organisms living in similar environments.
systematics
The reconstruction and study of evolutionary relationships.
phylogeny
The evolutionary history of an organism, including which species are closely related and in what order related species evolved; often represented in the form
cladistics
A taxonomic technique used for creating hierarchies of organisms that represent true phylogenetic relationship and descent.
shared derived character
In cladistics, character states that are shared by species and that are different from the ancestral character state.
polarize
In cladistics, to determine whether character states are ancestral or derived.
clade
A taxonomic group composed of an ancestor and all its descendents.
plesiomorphy
In cladistics, another term for an ancestral character state.
symplesiomorphy
In cladistics, another term for a shared ancestral character state.
homoplasy
In cladistics, a shared character state that has not been inherited from a common ancestor exhibiting that state; may result from convergent evolution or evolutionary reversal. The wings of birds and of bats, which are convergent structures, are examples.
paraphyletic
In phylogenetic classification, a group that includes the most recent common ancestor of the group, but not all its descendants.
The Linnaean hierarchy
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
extremophile
An archaean organism that lives in extreme environments; different archaean species may live in hot springs (thermophiles), highly saline environments (halophiles), highly acidic or basic environments, or under high pressure at the bottom of oceans.