They are single-cell organisms. Archaea live in extreme environments . They produce methane and cannot tolerate exposure to oxygen. Extreme thermophiles live in hot, sulfur rich and low pH environment, such as hot springs, geysers and fumaroles in the Yellowstone National Park. Cytoplasm is the viscous contents of a cell, including proteins, ribosomes, metabolites and ions.
Ribosomes are the sites of protein synthesis.
Plasma membrane is the cell membrane surrounding cytoplasm. It consists of phospholipid bilayer, associated proteins and carbohydrates. Phospholipid bilayer is also the basic constituent of other biomembranes. An eukaryotic cell contains several DNA molecules, located in the nucleus and mitochondria which are membrane-bound organelles. A prokaryotic cell contains a single DNA molecule, which has no specific boundary with the cytoplasm.