organismens

An organism is any individual living system that carries out the core processes of life. Organisms maintain organization through cellular structure, acquire and use energy through metabolism, grow and develop, respond to environmental stimuli, regulate internal conditions, and reproduce to pass genetic information to offspring. They range from single-celled microbes to complex multicellular beings.

All organisms rely on genetic material, typically DNA, to store information and guide growth and function. In energy terms, most organisms depend on metabolizing nutrients, either by photosynthesis or by consuming other organisms, and by releasing energy through cellular respiration. Reproduction can be asexual, sexual, or a combination, and development often follows a characteristic life cycle.

Biologists classify organisms within a framework that reflects evolutionary relationships. The highest level is three domains: Bacteria, Archaea, and Eukarya. Within Eukarya, groups include plants, animals, fungi, and various protists. Within bacteria and archaea, diversity is vast and includes many lineages with unique metabolisms. Taxonomy is a tool to organize knowledge about organisms, but it changes as new phylogenetic data emerge.

Organisms inhabit virtually every habitat on Earth and interact within ecosystems as producers, consumers, decomposers, and symbionts. They adapt to environments through genetic variation and natural selection, contributing to the planet’s biological diversity and resilience. Understanding organisms clarifies biology, medicine, ecology, and evolution, and underpins studies from microbiology to conservation.