Library · Microorganism
Bacterium
Make it clearer
A bacterium is a living thing made of a single cell, and that cell is put together differently from ours. Biologists call it a prokaryote, which means, literally, before the nucleus.
That is the underlying difference. Our cells keep their genetic material inside a nucleus, a kind of room with walls of its own. A bacterium has no such room: its genetic material sits in an area called the nucleoid, with no envelope separating it from the rest. It also has no membrane-bound organelles, the inner compartments our cells use to divide up the work.
What it almost always does have is a cell wall containing peptidoglycan, a mesh that gives the cell its shape and its strength, plus the enzymes devoted to building that mesh. All of it fits into something extremely small, on the scale measured in microns.
In brief
Bacteria are prokaryotic organisms: they keep their genetic material in a nucleoid rather than a membrane-bound nucleus, and they lack membrane-bound organelles.
Almost all prokaryotic cells carry peptidoglycan in the cell wall, along with the specific enzymes that build it, and that is one of the few features nearly all of them share.
All of that structure fits in a tiny space: bacterial cells are extremely small and are most conveniently measured in microns.
Sources (1)
- National Center for Biotechnology InformationStructure. Medical Microbiology, 4th editionPublished
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
Updated