Question

What are the three-domain classifications?

Answer 1

Classification of domain:

1. This system of classification was proposed by Carl Woese, Otto Kandler, and Mark Wheelis in 1990.
2. It is also known as the "Three Domains Classification" because it divides life forms into three domains.
3. In this classification, organisms are classified based on their appearance into six kingdoms and three domains.

Three-domain classification consists of:

1. Archaea: These include organisms that do not have a nuclear membrane, and their cell wall lacks peptidoglycan. Examples: Thermosphaera aggregans and Sulfolobus tokodaii.
2. Bacteria: They too are prokaryotes that lack a defined nuclear membrane, however, their cell membranes have peptidoglycan as a core component. Examples: Escherichia coli and Lactobacillus acidophilus.
3. Eukaryota: These are eukaryotic organisms that have a defined cell membrane. Their cell membranes are formed of proteins and lipids. Examples: fungi and protista.