Biology - Chapter 2: Classification of Living Organisms

Vocabulary flashcards for Biology Chapter 2, focusing on classification of living organisms.

Classification

The organization of living organisms into groups based on similarities in their characteristics and evolutionary basis.

Taxonomy

The branch of science concerned with classification, especially of organisms; systematics.

Taxonomic classification

A hierarchical system used to categorize organisms to the species level.

Domain

The broadest and largest taxon; includes Archea, Bacteria, and Eukarya.

Kingdom

A general taxon containing smaller groups called phyla (or divisions in plants and bacteria).

Phylum/Division

A taxon containing one or more related classes of animals (or divisions in plants & bacteria).

Class

Contains related orders.

Order

Contains related families sharing similar characteristics.

Family

Contains related genera, especially sharing a common attribute.

Genus

A group including closely related species.

Species

The most specific taxonomic level; a group of the same organisms that can interbreed and produce fertile offspring.

Binomial nomenclature

The formal naming system for species of living things, using a two-part scientific name of Latin origin (genus and species).

Archaea

Prokaryotes including the kingdom Archeabacteria, with cell walls lacking peptidoglycan, capable of surviving in harsh conditions.

Bacteria

Prokaryotes including the kingdom Eubacteria, with cell walls made of peptidoglycan, generally unable to survive in harsh conditions.

Prokaryotes

Organisms whose cells lack a nucleus and membrane-bound organelles.

Bacilli

Rod-shaped prokaryotes.

Cocci

Spherical prokaryotes.

Spirilla

Spiral and corkscrew-shaped prokaryotes.

Halophiles

Aerobic organisms that live in very salty environments.

Thermoacidophiles

Organisms that live in hot and acidic conditions.

Methanogens

Microorganisms that consume carbon dioxide and produce methane.

Gram positive

Bacteria that appear dark purple when stained, due to a thick peptidoglycan layer.

Gram Negative

Bacteria that appear pink when stained, due to a thin peptidoglycan layer and high lipid content.

Binary fission

A type of asexual reproduction in bacteria where the parent cell splits into two identical daughter cells.

Bacterial conjugation

The process by which one bacterium transfers genetic material to another through direct contact.

Viruses

Nonliving entities that can only reproduce inside a host cell.

Bacteriophages

Viruses that infect bacteria.

Capsid

The protein coat surrounding a virus.

Lytic cycle

Viral replication process where the virus hijacks the host's machinery to make new copies of the virus.

Lysogenic Cycle

Viral replication process where the viral genome is integrated into the host cell genome and copied along with the cell.

Retrovirus

Viruses that use RNA as their genetic material and employ reverse transcriptase to form DNA from RNA.

Vaccine

A preparation of weakened or killed pathogens or inactivated toxins that prompts the body to produce immunity.

Prions

Infectious protein particles that can cause disease.