Exam One Vocabulary Flashcards
(84 cards)
A branching diagram that represents a hypothesis about the evolutionary history of a group of organisms.
Phylogenetic Tree
A named taxonomic unit at any given level of classification.
Taxon
A phylogenetic tree containing a branch point representing the most recent common ancestor of all taxa in the tree.
Rooted
The evolutionary history of a species or group of related species.
Phylogeny
An approach to systematics in which organisms are placed into groups called clades based primarily on common descent.
Cladistics
Organism composed of cells that have a membrane-bound nucleus and several other membrane-bound compartments
Eukaryote
A group of taxa that consists of a common ancestor and some, but not all, of its descendants.
Paraphyletic
Structures in different species that are similar because of common ancestry.
Homologous structures
Technique using molecular evidence to identify phylogenetic relationships.
Molecular systematics
A group of taxa that includes distantly related organisms but does not include their most recent common ancestor.
Polyphyletic
In microscopy: A measure of the clarity of an image; it is the minimum distance two points can be separated an still be distinguished as tow points.
Resolution
Two part, latinized format for naming a species, consisting of the genus and specific epithet.
Binomial Nomenclature
In microscopy: the difference in light intensity between different parts of a sample and the background.
Contrast
A taxonomic level consisting Bacteria, Archaea, and Eukarya.
Domain
A scientific discipline concerned with naming and classifying the diverse forms of life.
Taxonomy
The representation on a phylogenetic tree of the divergence of two or more taxa from a common ancestor.
Branch point
In microscopy: the ratio of an object’s image size to its actual size.
Magnification
A group of taxa that consists of a common ancestor and all of its descendants.
Monophyletic
A character, shared by members of a clade, that originated in an ancestor that is not a member of that clade.
Shared ancestral character
Homologous genes found in different taxa as a result of speciation event.
Orthologous genes
Groups of organisms that share an immediate common ancestor and hence are each other’s closest relatives.
Sister taxa
The transfer of genes from one genome to another through mechanisms such as transposable elements, plasmid exchange, viral activity, and perhaps fusion of different organisms.
Horizontal gene transfer
A principle that states that when considering multiple explanations for an observation, one should first investigate the simplest explanation that is consistent with the facts.
Maximum parsimony
Distantly related taxon that possesses the ancestral state for all characters.
Outgroup
