Question

What are Archaebacteria? What unique characteristics do they possess?

Answer 1

Archaebacteria Sub-kingdom of the kingdom Prokaryote, which, on the basis of both RNA and DNA composition and biochemistry, differs significantly from other bacteria. They are thought to resemble ancient bacteria that first arose in extreme environments such as sulphur-rich, deep-sea vents. Archaebacteria have unique protein-like cell walls and cell membrane chemistry, and distinctive ribosomes. They include methane-producing bacteria, which use simple organic compounds such as methanol and acetate as food, combining them with carbon dioxide and hydrogen gas from the air, and releasing methane as a by-product. The bacteria of hot springs and saline areas have a variety of ways of obtaining food and energy, including the use of minerals instead of organic compounds. They include both aerobic and anaerobic bacteria. Some hot springs bacteria can tolerate temperatures up to 88°C (190°F) and acidities as low as pH 0.9. One species, Thermoplasma, may be related to the ancestor of the nucleus and cytoplasm of the more advanced eukaryote cells. Some taxonomists consider archaebacteria to be so different from other living organisms that they constitute a higher grouping called a domain.