Organizing Life

These flashcards cover key concepts from Chapter 19 on the organization of life, focusing on taxonomy, classification systems, and phylogenetics.

Taxonomy

The branch of biology that identifies, names, and organizes biodiversity into related categories.

Binomial nomenclature

A system of naming organisms with a two-part name consisting of the genus and species.

Phylogeny

The evolutionary history of a group of organisms.

Cladistics

A method that uses shared, derived traits to develop a hypothesis of evolutionary history.

Ancestral traits

Traits present in all members of a group, inherited from a common ancestor.

Derived traits

Traits present in some members of a group but absent in the common ancestor, useful for clarifying evolutionary relationships.

Domain

The highest taxonomic rank, used to classify life forms into three categories: Bacteria, Archaea, and Eukarya.

Supergroup

A classification level that lies below domain and above kingdom, used especially for protists.

DNA barcoding

A method used to identify species by comparing a short fragment of DNA sequence to a database.

Phylum

A level of classification that groups together organisms sharing a high degree of similarity.

Homologous structures

Anatomical features in different organisms that stem from a common ancestor.

Analogous structures

Structures that serve similar functions in different species but do not share a common ancestor.

Molecular clock

A method that uses mutation rates in DNA to estimate the time of evolutionary change.

Parsimony

The principle that the simplest explanation or path that requires the least number of assumptions is generally the best.

Species

The most exclusive taxonomic category, containing only one type of organism.

Evolutionary tree

A diagram that represents the relationships and divergences between different species.