• Life Sciences

a large domain of prokaryotic micro-organisms. They are typically a few micrometres in length having a wide range of shapes, ranging from spheres called cocci, rod-shaped, called bacilli, slightly curved or comma-shaped, called vibrio, spiral-shaped, called spirilla, to tightly coiled, called spirochaetes. A small number of species even have tetrahedral or cuboidal shapes. Bacteria are present in most habitats on Earth, growing in soil, acidic hot springs, radioactive waste, water, and deep in the Earth's crust, as well as in organic matter and the live bodies of plants and animals.