He Monera kingdom Are the set of unicellular organisms that are much smaller, simpler and more basic than the cells of other life forms. It is considered by many scientists as the oldest form of life on Earth, so they are the ancestors of all other types of life that have evolved ever since.
These cells have no nucleus, no nuclear membrane, the chromosome is unique and circular, and they are also losing many of the organelles or parts commonly found in other cells. For this reason, it is believed that this kingdom is very different from other ways of life.
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This kingdom contains two very different groups, eubacteria and archaebacteria. Both usually have cell walls that surround the cell membranes, which contain DNA rings slightly attached to the membrane but without organelles.
Both types come in the form of a spherical, rod-like and elongated propeller, while archaea occasionally also has triangular or other shapes.
The monera kingdom is made up of all bacteria, which are universal since they can be found everywhere, even some live in the air you breathe. There are some of the bacteria that can cause disease and there are others that are essential for our survival. Bacteria help to break down dead matter and also food into the digestive system.
Some have the ability to move using their flagella, but others can not move by themselves. There are a few who can make their own food and feed on decaying dead matter.
10 Main features of the monera kingdom
1 - Reproduction is asexual
Most of the Prokaryotes Are reproduced asexually by binary fission. The cell duplicates itself and a DNA molecule passes into a newly formed cell, these two cells being genetically identical.
Binary fission does not allow bacteria to acquire genetic diversity, this diversity is necessary for bacteria to withstand changing environments.
Bacteria have the ability to mix genes through various processes. These processes include conjugation, transformation and transduction.
2- Perform particular movements
Bacteria move with hair-like extensions known as flagella, which are longer than cilia but smaller in number. The flagella in prokaryotes are much thinner than in eukaryotes and attach to the surface of the cell rather than to the cytoplasm.
They can be found on the front of the back of the bacteria, at both ends, or occasionally on the entire surface. Flagellum sweeps are a propeller movement to help the bacteria move.
Bacteria can also move through the secretion of slime, and they slide along the surfaces. However, other bacteria move by axial filaments. The axial filaments cause the cell to rotate and move like a corkscrew.
3- They have means of defenses
Although not obvious, organisms in the kingdom monera do have some means of defense. In some species of bacteria, there is something called a capsule formed by polysaccharides that protects the bacterium from phagocytes (such as white blood cells) and desiccation.
Certain bacteria also have means of movement that they can use to get away from things that could damage them.
4- They are resistant
When living conditions become too hard to support bacteria, they can develop a tough protective wall around their DNA and a small fragment of cytoplasm. This creates a highly resistant and latent structure that is called endospora. The rest of the cell that remains can die.
Fortunately for the bacteria, the endospora can withstand even years of frostbite, or drought. When the conditions become suitable for the bacteria to be active again, the endospore becomes an active cell again.
Cyanobacteria form resistant spores called akinetes, which are enlarged cells around which thickened outer walls develop. These akinetes are resistant to heat, freezing and drought, so that cyanobacteria can survive harsh environmental conditions.
They work practically the same as the bacterial endospores, but they do not always look the same, and although they are resistant they are not as resistant as the endospores.
5- They require some nutrition
Like all organisms, prokaryotes must construct complex molecules from simple molecules. These require carbon and energy to create the life molecules of carbohydrates, proteins, lipids and nucleic acids.
Prokaryotes obtain carbon and energy from a variety of sources, and can be autotrophic or heterotrophic. All bacteria also need nitrogen, sulfur, phosphorus, inorganic salts and micronutrients.
Some prokaryotes are autotrophs and produce their own food by photosynthesis or chemosynthesis. Others get their energy from inorganic compounds such as hydrogen sulfide, ammonia and iron, and use carbon dioxide as a source of carbon, which is known as chemosynthesis.
6- Different types of breathing
Breathing in these organisms varies, they can be forced aerobes: organisms must have organisms to survive; Mandatory anaerobes: organisms can not survive in the presence of oxygen; Or facultative anaerobes: these organisms can survive with or without oxygen.
Some bacteria are autotrophic organisms, bacteria that get carbon from carbon dioxide. In turn, organisms that use light to obtain their energy are known as photoautótrofos.
Chemoautotrophs are bacteria that receive their energy from inorganic compounds such as hydrogen sulfide and the use of energy to execute the activities of the cell.
The rest of the bacteria are heterotrophic, organisms that obtain carbon when ingesting organic molecules of organisms in decomposition or to live by or in another organism known like host.
To get energy from molecules such as sugars, bacteria must use fermentation or cellular respiration. Some species of bacteria go through the process of cellular respiration.
This is a more complex process that does not need oxygen, and the energy of organic molecules are more efficient in creating ATP . Carbon dioxide and water are the most produced by-products.
7- Prokaryotes lack organelles
With the exception of Ribosomes , Prokaryotes lack organelles. Prokaryotic cells are simple cells that do not have a membrane-bound nucleus or organelles. They have DNA and ribosomes.
They have no organelles, since the cytoplasm performs the metabolic work, and technically only circular DNA is found in the nucleoid region and some ribosomes in a prokaryotic cytoplasm (which are not organelles because they are a cell structure that is protected by a membrane) .
8- Enrich the soil
Bacteria also enrich the soil. For example, nitrogen fixers convert nitrogen from air to nitrate, which plants need to live, and a number of cyanobacteria help to fix nitrogen levels in the atmosphere.
These photosynthetic bacteria also contribute large amounts of oxygen to the atmosphere. Bacteria also break down matter and is used for fertilizer.
9- They are found in diverse habitats
The monera kingdom lives on land and soil, especially where there is water, but is found everywhere: in the hot springs, under the ice, deep in the deep ocean, in the deserts, or in the body of plants and Animals, and countless more habitats. They are present in both living and non-living environments.
10- They have special features
The DNA fragments are in the form of plasmids. Through these processes the bacteria can obtain new traits that they could not obtain only through binary fission. These traits may include the ability to resist change in acidity, temperature and also have the ability to resist antibiotics.
Other characteristics of the monera kingdom
- They are primitive organisms.
- They can be good or bad. Bad can infect animals, humans and plants. Good ones are called beneficial bacteria, rather than pathogenic bacteria, and are considered to be the majority.
- The DNA is double stranded, suspended in the cytoplasm of the organism, called nucleotide.
- Circulation is through diffusion.
- They are about 1 micrometer in size.
- The cell structure of monera is mainly unicellular.
- These organisms are the simplest prokaryotic cell structures.
- Many bacterial species contain DNA rings called plasmids.
- The cytoplasm is enclosed by the plasma membrane beneath the cell wall.
- The plasma membrane is made up of lipids and proteins.
References
- Biology Team (2004). The Five Kingdoms: Monera. Kids Biology. Retrieved from: kidsbiology.com.
- Reference Team (2016). What is Monera? Reference. Retrieved from: reference.com.
- Nancy T Trader (2016). Prokaryotes. Quora. Recovered from: quora.com.
- Tutor Vista Team (2017). Kingdom Monera. Tutor Vista. Retrieved from: biology.tutorvista.com.
- Sean Moores (2010). The Kingdom Monera. CBV. Retrieved from: cbv.ns.ca.