The Archaea
Introduction
All living organisms can be classified into The Three Domains of Life, Archaea, Bacteria or Eukarya. See Figure 1 below.
Archaea formerly known as archaebacteria are prokaryotic microorganisms meaning they have no cell nucleus or any other membrane bound organelles in their cells. Archaea are comparable in size to bacteria. The single cellular microorganism, Archaea, can live in a range of environments including those of extreme conditions.
This report outlines Archaea as prokaryotes, the evolutionary relationship of Archaea to eukaryotes and bacteria, the habitats of Archaea and the role of Archaea in the digestive tract of termites.
Figure 1: The Three Domains of Life (Speer, 1998)
Reasons that the Archaea are classified as Prokaryotes
Prokaryotic cells are type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles (Campbell, 2009). Archaea cells do not have a nucleus or other organelles therefore they are classified as prokaryotic cells.
The Three Domains of Life, Bacteria, Archaea and Eukarya were founded based on genetic criteria, however biochemical properties also indicate that Archaea an independent group within the prokaryotes, shares traits with both bacteria and eukaryotes (Neiderberger, 2014). See Table 1.
Table 1: Shared Traits Among bacteria, Archaea and Eukarya (Neiderberger, 2014)
Trait Bacteria Archaea Eukarya
Cell wall All bacteria contain peptidoglycan in cell walls. Various types of cell walls exist. Lacking peptidoglycan. Lack peptidoglycan.
Fatty Acids Produce membrane lipids consisting of fatty acids linked by ester bonds to a molecule of glycerol. No ester linked lipids. Archaea have ether bonds connecting fatty acids to molecules of glycerol. Pro...
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...t of the termite houses a complex microbial community, containing microorganisms from the Three Domains of Life, Archaea, Bacteria and Eukaryota. The Archaea species methanobrevibacter is located in the digestive tract of termites, producing methane by the process of metanogenesis.
The relationship between Archaea and protists (eukaryotic microorganisms) inside the gut of the termite is essential for the digestion of cellulose and enhance cellulose fermentation. Hydrogen and carbon dioxide are produced by protists, and can be used by Archaea as a source of energy. Methane is formed as a byproduct of this process, the elimination of the hydrogen enables the protists to maintain an optimal pH to for favourable conditions for decomposition to occur.
Conclusion
Through contributions of Woese and Fox, our undertandig of life on earth, and the methods in which we….
(n.d.). Phenotypic methods of classifying microorganisms describe the diversity of bacterial species by naming and grouping organisms based on similarities. The differences between Bacteria, Archaea and Eukaryotes are basic.
Linking with the idea of hydrothermal vents being a 'reactor' for RNA hydrothermal vents rely on chemical energy from geothermal vents to sustain a organisms. Swarms of bacteria thrive in this environment which acts as an interface between the high temperature vents and cold oxygenated seawater. The bacteria thrive on gases produced by the vents such as methane and use these chemicals to produce simple organic molecules to support the local ecosystem in a similar way to plants using photosynthesis. Wachtershauser has proposed that a biochemical cycle grew and assembled the first living cell.
The start of any evolutionary story told about us lies within the origin of the eukaryote cell. This remarkable event consisted of a revolution of cell type matched in momentousness by the arrival on the biological scene of the prokaryote (O’Malley). Bacteria had a couple billion years head start on eukaryotes and have given rise to many biochemical processes that are essential to the ecosystem (Wernergreen). One organism living within another defines endosymbiosis. Nobody can say the exact origin of the eukaryote cell. The endosymbiosis theory dates back to the earliest 20th century and devotion to different models of its origins is strong and adamant (O’Malley).
The domain for Klebsiella is Bacteria, it is in the Proteobacteria phylum, Gammaproteobacteria class, Enterobacteriales is the Order, the family is Enterobacteriacaea, the Genus is Klebsiella, and finally the species is Klebsiella pneumonia.
what help create all the living things we see everyday. Lipids are found in all membranes, mainly
14. Erucic acid is a long-chain unsaturated fatty acid. Like oleic acid, it suppresses the creation of VLCFSAs, but is much more
Bacterial cells, like plant cells, are surrounded by a cell wall. However, bacterial cell walls are made up of polysaccharide chains linked to amino acids, while plant cell walls are made up of cellulose, which contains no amino acids. Many bacteria secrete a slimy capsule around the outside of the cell wall. The capsule provides additional protection for the cell. Many of the bacteria that cause diseases in animals are surrounded by a capsule. The capsule prevents the white blood cells and antibodies from destroying the invading bacterium. Inside the capsule and the cell wall is the cell membrane. In aerobic bacteria, the reactions of cellular respiration take place on fingerlike infoldings of the cell membrane. Ribosomes are scattered throughout the cytoplasm, and the DNA is generally found in the center of the cell. Many bacilli and spirilla have flagella, which are used for locomotion in water. A few types of bacteria that lack flagella move by gliding on a surface. However, the mechanism of this gliding motion is unknown. Most bacteria are aerobic, they require free oxygen to carry on cellular respiration. Some bacteria, called facultatibe anaerobes can live in either the presence or absence of free oxygen. They obtain energy either by aerobic respiration when oxygen is present or by fermentation when oxygen is absent. Still other bacteria cannot live in the presence of oxygen. These are called obligate anaerobes. Such bacteria obtain energy only fermentation. Through fermentation, different groups of bacteria produce a wide variety of organic compounds. Besides ethyl alcohol and lactic acid, bacterial fermentation can produce acetic acid, acetone, butyl alcohol, glycol, butyric acid, propionic acid, and methane, the main component of natural gas. Most bacteria are heterotrophic bacteria are either saprophytes or parasites. Saprophytes feed on the remains of dead plants and animals, and ordinarily do not cause disease. They release digestive enzymes onto the organic matter. The enzymes breakdown the large food molecules into smaller molecules, which are absorbed by the bacterial cells. Parasites live on or in living organisms, and may cause disease. A few types of bacteria are Autotrophic, they can synthesize the organic nutrients they require from inorganic substances. Autotrophic bacteria are either photosynthetic or Chemosynthetic. The photosynthetic bacteria contain chlorophyll that are different from the plant chlorophyll. In bacterial photosynthesis, hydrogen is obtained by the splitting of compounds other than water.
There are many functions lipids have. One of the main functions lipids are structural components in the cell. Lipids make up approximately 50% of the mass of most cell membranes. The lipids that are found in the cell membrane are called phospholipid. Phospholipid are the predominant lipids of cell membrane. Phospholipids aggregate or self-assemble when mixed with water, but in a different manner than the soaps and detergents. Because of the two pendant alkyl chains in phospholipids and the unusual mixed charges in their head groups, micelle formation is unfavorable relative to a bilayer structure.
They also describe microbes as organisms that are often too small to be seen without the aid of a microscope. Microbes, also known as microorganisms, can be broken down into four classifications that are bacteria, viruses, fungi, and protozoa.
Prokaryotic cells do not have a nucleus. The chromosomes which are found in prokaryotes are usually spread in the cytoplasm. In eukaryotic cells the chromosomes remain together inside the nucleus and there is a clear nuclear membrane that is surrounding the nucleus.
Microbial decomposition releases nutrients into the environment that are needed by other organisms. Microbes are also involved in the cycling of many other important compounds in — and between — ecosystems, including oxygen, carbon and nitrogen. Many microbes use the energy of sunlight to convert carbon dioxide to oxygen, which we need to breathe. As they do this, they create new organic material — themselves — which are then eaten by other organisms. In this way, the cycling of nutrients and energy
Every organism requires a specific environment in order to survive. Bacteria alike, different types of bacteria are able to survive and reproduce in different types of environment. Some factors that affect the growth of bacteria include temperature, presence of certain gases and pH of the medium it is in.
It is a single-celled organism that is not visible to the human eye, which means it can only be seen with a microscope. Bacteria are classified as Prokaryotes. They make their own food from the sunlight and can absorb food from the materials that they live on.
Domains may be considered to be connected units, which are to varying extents independent in terms of their structure, function and folding behaviour. Each domain can be described by its fold. While some proteins consist of a single domain, others consist of several or many. A number of globular protein chains consist of two or three domains appearing as 'lobes'. In other cases the domains may be of very different nature- for example some proteins located in cell membranes have a globular intracellular or extracellular domain distinct from that which spans the membrane.
Prokaryotes include several kinds of microorganisms, such as bacteria and cyanobacteria. Eukaryotes include microorganisms as fungi, protozoa, and simple algae. Virus cells often consist of just a nucleic acid either DNA or RNA in a protein capsule. Viruses are considered neither prokaryotes nor eukaryotes because they lack the characteristics of living things, except the ability to replicate (which they accomplish only in living cells).