Bacteria are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in …

Bacterial infections are caused by harmful bacteria and can affect many parts of your body. They can be minor or serious and are often treated with antibiotics.

Journey from the human scale into a microscopic world to explore five of the most common bacterial forms.

Nov 7, 2025 · Bacteria are microscopic single-celled organisms that live in almost every environment on Earth, from deep-sea vents to human digestive tracts. They are prokaryotes, …

Aug 8, 2025 · In 1838, the German naturalist Christian Gottfried Ehrenberg called them ‘bacteria’, from the Greek word ‘baktḗria’, meaning ‘little stick’. Later, Robert Koch’s research, famously …

Bacteria are microbes with a much simpler cell structure than many other organisms, but they are by no means simple. The more scientists look, the more they understand about how complex …

Oct 4, 2019 · 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. …

4 days ago · Bacteria are small single-celled organisms. Bacteria are found almost everywhere on Earth and are vital to the planet's ecosystems. Some species can live under extreme …

Oct 19, 2023 · Bacteria are microscopic infectious agents that have a long history of infecting humans, but they also play a vital role in supporting human health.

Apr 18, 2025 · These tiny, single-celled organisms—bacteria—are among the most ancient, numerous, and influential forms of life on Earth. They are so small that millions can live in a …