1. Domain Archaea
These are the most primitive organism on Earth. They are prokaryotes but their cell wall dose not contain peptidoglycan but is made of various polypeptides and proteins. Their rRNA (ribosomal RNA) resembles more to eukaryotes than to bacteria. Their cell membrane contain unique lipids which enable them to live in extreme environment. " hot spring, salt lakes, and acidic of alkaline waters." However, they also exist in more common environment like soil and oceans. Some archaea obtain energy from inorganic compounds such as sulphur or ammonia. Their other groups perform photosynthesis bu do not produce oxygen.
Diversity in domain archaea.
[Source of Photo](https://images.app.goo.gl/CCgvMyGUfM8djGjD6)
There is one kingdom in domain Archaea, kingdom archaebacteria (ancient bacteria).
EXAMPLES of Archaeabacteria include Methanogens (produce mthane as a by-product of their metabolism), Thermophiles (found in hot springs), Acidophiles ( found in extremely acidic environments).
All data collected from my book of Biology.