Archaea and bacteria (eubacteria) are single-celled organisms that do not have a nucleus or organelles. Archaea have a distinct evolutionary history and biochemistry compared with bacteria.
Archaea - a domain of single-celled microorganisms. These microbes are prokaryotes. Archaea can survive in extreme and harsh environments like hot springs, salt lakes, marshlands, oceans, gut of ruminants and humans.
Bacteria - a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a number of shapes, ranging from spheres to rods and spirals. Eubacteria are ubiquitous and are found in soil, hot springs, radioactive waste water, Earth's crust, organic matter, bodies of plants and animals, etc.
Vitamins are a group of substances that are needed for normal cell function, growth, and development. There are 13 essential vitamins:
Vitamin A (retinol, retinal, 4 carotenoids)
Vitamin C (ascorbic acid)
Vitamin D (D3 - Cholecalciferol, D2 - Ergocalciferol)
Vitamin E (tocopherols, tocotrienols)
Vitamin K (phylloquinone, menaquinones)
Vitamin B1 (thiamine)
Vitamin B2 (riboflavin)
Vitamin B3 (niacin)
Vitamin B5 (pantothenic acid)
Vitamin B6 (pyridoxine, pyridoxal, pyridoxamine)
Vitamin B7 (biotin)
Vitamin B9 (folic acid)
Vitamin B12 (cyanocobalamin)
Fat-soluble vitamins are stored in the body's fatty tissue: vitamins A, D, E, K.
Water-soluble vitamins - the body must use almost all water-soluble vitamins right away - vitamins B1, B2, B3, B5, B6, B7, B9 and C. Vitamin B12 is the only water-soluble vitamin that can be stored in the liver for many years.