Archaea (/ ɑːrˈkiːə / ⓘ ar-KEE-ə) is a domain of organisms. Traditionally, Archaea only included its prokaryotic members, but this has since been found to be paraphyletic, as eukaryotes are now known to have evolved from archaea.

Mar 27, 2025 · Archaea are microorganisms that define the limits of life on Earth. They were originally discovered and described in extreme environments, such as hydrothermal vents and terrestrial hot springs. They were also found in a diverse range of highly saline, acidic, and anaerobic environments.

Archaea share some characteristics with known pathogens that may reflect the potential to cause disease. Such characteristics include ample access to a host (i.e., opportunity) and capabilities for long-term colonization and coexistence with endogenous flora in a host.

Oct 8, 2023 · Archaea is a domain of life, together with Bacteria and Eukarya, containing single-celled prokaryotes other than bacteria. They are the oldest life-form known to exist. The name Archaea is derived from the Greek word ‘ARCHAIOS’ meaning primitive.

Mar 13, 2019 · Archaeans are extremely small microbes that must be viewed under an electron microscope to identify their characteristics. Like bacteria, they come in a variety of shapes including cocci (round), bacilli (rod-shaped), and irregular shapes.

Oct 19, 2023 · Archaea, formerly known as ‘archaebacteria,’ are a group of single-celled, prokaryotic organisms belonging to the domain Archaea. Apart from Archaea, Bacteria and Eukarya are the other two domains of life that currently exist. Until the 20th century, all living organisms were classified as plants or animals.

archaea, A group of prokaryotes whose members differ from bacteria, the most prominent prokaryotes, in certain physical, physiological, and genetic features. The archaea may be aquatic or terrestrial microorganisms. They exhibit a diversity of …

Mar 27, 2025 · Halophilic archaeans, which include Haloarcula marismortui, a model organism used in scientific research, are thought to have acquired the unique set of genes for the methylaspartate pathway via a process known as horizontal gene transfer, in which genes are passed from one species to another.

Archaea is a group of prokaryotic life forms distinct from bacteria forming a separate domain of life. They possess pseudo-peptidoglycan cell wall, archaeol plus ether-linked plus highly branched isoprenoid chain lipids in their cell membrane with no nuclei or cell organelles. They have a ubiquitous distribution and are widely known extremophiles.

Sep 16, 2023 · Archaebacteria: Sole organisms that can survive in extreme habitats & archaeans are considered the third domain of life. Learn about the domain Archaea here.