Bacteria | Under The Microscope

Bacteria are single-celled microorganisms that exist in their millions, in every environment, literally everywhere, though small, they are complex and robust, and they can survive in extreme conditions. Covering the whole spectrum, from the extremely cold to the extremely hot environments, They even live in our guts! Bacteria are thought to have been the first organisms to appear on earth, about 4 billion years ago. And as such they earned the right to their own domain of life, Eubacteria, or “true” bacteria. Bacteria are classified as prokaryotes, which means they have no nucleus. Generally bacteria are surrounded by two protective coverings: an outer cell wall and an inner cell membrane. Certain bacteria, like the mycoplasmas, do not have a cell wall at all. Some bacteria may even have a third, outermost protective layer called the capsule. Many bacteria have Whip-like extensions covering their surface. — long ones called flagella used for movement, and short ones called pili used to stic