domains of life and species

Domains of Life

The primary categories which classify all living organisms: Bacteria, Archaea, and Eukarya.

Scientific nomenclature

The system used to name and classify living organisms, primarily following the Linnaean system.

Linnaean system

A hierarchical system of classification for species, created by Carl Linnaeus, which uses a two-part naming system.

Prokaryotes

Simple organisms without a defined nucleus; examples include bacteria and archaea.

Eukaryotes

Complex organisms with internal cellular structures, including a nucleus and membrane-bound organelles.

Last Universal Common Ancestor (LUCA)

The most recent common ancestor of all current life on Earth.

16S ribosomal RNA

A component of a ribosome used in the phylogenetic classification of organisms due to its slow rate of evolution.

Phylogeny

The study of the evolutionary history and relationships among individuals or groups of organisms.

Endosymbiosis

A process in which one organism lives inside another, leading to the development of complex cells like eukaryotes.

Species

A group of closely related individuals capable of interbreeding to produce fertile offspring.

Prezygotic reproductive isolation

A mechanism that prevents mating or fertilization between species.

Taxonomy

The science of naming, describing, and classifying living organisms.

Systematics

The branch of biology that deals with classifying organisms and determining their evolutionary relationships.

Carl Linnaeus

A Swedish botanist who developed the modern system of naming organisms.

Common ancestor

An ancestral species from which later species have evolved.

Ecological specialization

The adaptation of an organism to a specific environment, often leading to most species excelling in that niche.

Chloroplast

An organelle found in plant cells and some protists that conducts photosynthesis.

Mitochondria

The powerhouses of the cell that produce energy through cellular respiration.

Evolutionary landscape

A conceptual model illustrating how evolutionary processes shape population adaptation and survival.

Simplification in evolution

The process by which some organisms lose complex structures and become more specialized over time.

Metabolic pathways

Series of enzymatic reactions in cells that lead to the conversion of substrates into products.

Universal genetic code

The set of rules by which information encoded in genetic material is translated into proteins.

Cichlid fish

A diverse group of fish species found primarily in African Great Lakes, known for their reproductive isolation based on color preferences.