organisms
Life forms overall
Organisms are living things—entities that grow, reproduce, respond to stimuli, and maintain internal processes.
The term covers everything from bacteria to blue whales: The pond contains thousands of microscopic organisms.
In biology, organism distinguishes individual living units from populations, species, or ecosystems.
Figuratively, any complex system with interdependent parts may be called an organism: the social organism.
Nucleus-free single-celled organisms
- archaeaThird domain of life
- protozoaSingle-celled eukaryotic organisms
- virusesSubmicroscopic infectious particles
- planktonDrifting marine microlife
algae · amoeba · paramecium · euglena · diatoms · microbes · pathogens · microbiota
Range of life forms
- floraPlants of a region
- faunaAnimal life collectively
- variationChange from a norm
- endemicNative to one area
exotic · endangered · threatened · extinction · conservation · habitats · genetic diversity · populations
Multicellular mobile organisms
- plantsPhotosynthesizing rooted organisms
- mammalsHair-bearing, milk-producing animals
- birdsEgg-laying flying vertebrates
- reptilesCold-blooded scaly vertebrates
amphibians · fish · insects · trees · shrubs · vertebrates · invertebrates · megafauna
Finest taxonomic rank
- taxonomyScience of categorical arrangement
- classificationSystematic grouping by traits
- anatomyStudy of organism structure
- physiologyScience of bodily functions
genetics · morphology · cellular · metabolism · reproduction · heredity · phylogeny · homology
Differential reproductive success
- adaptationFitting to new conditions
- speciationFormation of distinct species
- mutationPermanent DNA alteration
- genetic driftRandom allele frequency change
common descent · phylogeny · ancestry · fossils · paleontology · Darwinism · survival of the fittest · reproductive success
Interconnected organisms and surroundings
- habitatOrganism's natural environment
- nicheRecessed wall space
- populationAll inhabitants combined
- communityCollective of connected people
biosphere · symbiosis · competition · predation · food web · keystone species · carrying capacity · succession
Coming into the world
- growthIncrease in size
- developmentProgress toward maturity
- reproductionCopying or procreation
- deathCessation of life
aging · maturation · senescence · metamorphosis · gestation · regeneration · homeostasis · juvenile
bacteria
Nucleus-free single-celled organisms
- archaeaThird domain of life
- protozoaSingle-celled eukaryotic organisms
- virusesSubmicroscopic infectious particles
plankton · algae · amoeba · paramecium · euglena · diatoms · microbes · pathogens · microbiota · yeast
biodiversity
Range of life forms
endemic · exotic · endangered · threatened · extinction · conservation · habitats · genetic diversity · populations · adaptation
animals
Multicellular mobile organisms
- plantsPhotosynthesizing rooted organisms
- mammalsHair-bearing, milk-producing animals
- birdsEgg-laying flying vertebrates
reptiles · amphibians · fish · insects · trees · shrubs · vertebrates · invertebrates · megafauna · wildlife
species
Finest taxonomic rank
- taxonomyScience of categorical arrangement
- classificationSystematic grouping by traits
- anatomyStudy of organism structure
physiology · genetics · morphology · cellular · metabolism · reproduction · heredity · phylogeny · homology · biochemistry
natural selection
Differential reproductive success
- adaptationFitting to new conditions
- speciationFormation of distinct species
- mutationPermanent DNA alteration
genetic drift · common descent · phylogeny · ancestry · fossils · paleontology · Darwinism · survival of the fittest · reproductive success · cladistics
ecosystem
Interconnected organisms and surroundings
- habitatOrganism's natural environment
- nicheRecessed wall space
- populationAll inhabitants combined
community · biosphere · symbiosis · competition · predation · food web · keystone species · carrying capacity · succession · biotic
birth
Coming into the world
- growthIncrease in size
- developmentProgress toward maturity
- reproductionCopying or procreation
death · aging · maturation · senescence · metamorphosis · gestation · regeneration · homeostasis · juvenile · adult
organismsmachines
Devices that perform tasks
robots · constructs · artifacts · automatons · mechanisms
- whole organism
- living organisms
- soil organisms
- genetically modified organismsLifeforms with altered DNA
- tiny organisms
- single-celled organismsOrganisms lacking multicellularity