Bacterium Definition & Meaning - Merriam-Webster
The meaning of BACTERIUM is any of a domain (Bacteria) of chiefly round, spiral, or rod-shaped single-celled prokaryotic microorganisms that typically live in soil, water, organic matter, or the bodies of plants and animals, that make their own food especially from sunlight or are saprophytic or parasitic, are often motile by means of flagella ...
Bacteria - Wikipedia
Bacteria (/ b æ k ˈ t ɪər i ə / ⓘ; sg.: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms .
Bacteria | Cell, Evolution, & Classification | Britannica
3 days ago · Bacteria are microscopic single-celled organisms that inhabit virtually all environments on Earth, including the bodies of multicellular animals. Bacteria lack a membrane-bound nucleus and other internal structures.
Bacteria - Definition, Shapes, Characteristics, Types & Examples
Oct 4, 2019 · Bacteria Definition. Bacteria are single-celled microorganisms with prokaryotic cells, which are single cells that do not have organelles or a true nucleus and are less complex than eukaryotic cells. Bacteria with a capital B refers to the domain Bacteria, one of …
Bacteria: Definition, Types, Benefits, Risks & Examples
Dec 2, 2022 · Bacteria are microscopic living organisms that have only one cell. The word for just one is “bacterium.” Millions (if not billions) of different types of bacteria can be found all over the world, including in your body. They’re on your skin and in your airways and mouth.
What are bacteria and what do they do? - Medical News Today
Feb 12, 2019 · Bacteria are microscopic, single-celled organisms that exist in their millions, in every environment, both inside and outside other organisms. Some bacteria are harmful, but most serve a useful...
Bacteria: Definition & Characteristics With Examples & Diagram
Feb 2, 2023 · Bacteria are disease-causing, microscopic, single-celled organisms with prokaryotic cell structures. They do not have membrane-bound organelles, including a true nucleus. Being the lowest and simplest form of life, they are found almost everywhere on earth and thus, are the most dominant living creature.
Bacteria - Definition and Examples - Biology Online Dictionary
Jul 24, 2022 · Bacteria are microscopic, single-celled organisms belonging to Kingdom Monera that possess a prokaryotic type of cell structure, which means their cells are non-compartmentalized, and their DNA (usually circular) can be found throughout the cytoplasm rather than within a membrane-bound nucleus.
BACTERIUM | definition in the Cambridge English Dictionary
a type of very small organism that lives in air, earth, water, plants, and animals, often one that causes disease: an illness caused by bacteria in drinking water. The bacterium Streptococcus …
Bacteria - Definition, Structure, Types & Infections - Rs' Science
Bacteria (singular: Bacterium) are single-celled microorganisms. The cell structure of bacteria is much simpler than that of eukaryotic cells. There are no nucleus or membrane-bound organelles in a bacterial cell. Thus, bacteria are classified as “Prokaryotic cells”.