Unit 5: Classification & Evolution Vocabulary (OL)

Vocabulary terms & definitions for classification & evolution

Taxonomy

The classification of living things.

Classification

The process of grouping living organisms based on their characteristics.

Organism

Any living thing.

Domain

The highest and broadest taxonomic level of the biological classification system.

Kingdom

A set of organisms that share a similar cellular structure and level of complexity.

Genus

Classification grouping that consists of a number of closely related species.

Species

A group of organisms that are physically similar and can mate with each other and produce fertile offspring.

Unicellular

An organism that is composed of one cell.

Multicellular

An organism that is composed of more than one cell.

Prokaryotic

Organisms whose cells lack a nucleus.

Eukaryotic

Organisms whose cells have a nucleus.

Sexual reproduction

Reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents.

Asexual reproduction

Reproductive process that involves only one parent & produces offspring that are identical to the parents.

Autotroph

An organism that produces its own food.

Heterotroph

An organism that cannot make its own food.

Binomial nomenclature

A two-part scientific name consisting of an organism’s genus & species.

Dichotomous key

A scientific tool used to identify different organisms based on their observable traits.

Evolution

The change in heritable traits of populations over time.

Scientific Theory

Idea based on facts that have been repeatedly confirmed through observation and experiment.

Charles Darwin

A British naturalist who proposed the theory of evolution by natural selection.

Adaptation

A trait that makes an organism more likely to survive in its environment.

Extinction

The dying out of a species.

Fitness

A measure of the success of an individual or genotype in a given population at a given time.

Fossil

Preserved remains of plants and animals whose bodies were buried in sediments under ancient seas, lakes and rivers.

Fossil Record

A recording of history made out of layers of fossils.

Relative Dating

Method to determine the age of a fossil by comparing which layer it was found in.

Radioactive Dating (Absolute)

Method used by scientists to determine the age of rocks and minerals from the amount of radioactivity it contains.

Natural Selection

Process by which individuals that are better suited/adapted for their environment survive.

Artificial selection

A process used by humans to develop new organisms with desirable characteristics.

Population

A group of individuals of the same species that live in the same area and interact with one another.

Variation

Differences in physical traits among individuals within a population or species.

Homologous Structures

Physical traits of different species that share a similar structure but different function.

Vestigial Structures

Structure that is reduced in size and no longer has a function in a modern species.

Cladogram

A diagram that shows relationships between species based on observable physical characteristics.