a study between two groups of the Kingdom Monera: (true bacteria) Eubacteria and Cyanobacteria (blue-green algae). most experts consider this group as subkingdoms and others think of them as a division of the Kingdom Monera.
Eubacteria
Bacteria (singular bacterium), which includes a small group of eubacteria, relatively simple, single-celled organisms. They've been here longer and wider than other organisms. They are found in almost all habitats such as in air, water, soil, in extreme temperatures and in harsh chemical environments. Some bacteria can perform photosynthesis, using H2S instead of H2O, as the electron source, but most are heterotrophic, absorbing nutrients from the environment around him.
These bacteria are called "prokaryotes", which comes from the Greek for "prenucleus". any one characteristic that distinguishes them is that they do not contain membrane bound "organelles". Especially the genetic material they are not bound by a nuclear envelope. Bacteria do not have the chromosome, as described in the last term. Instead, their genetic material is a single circular loop of DNA (Figure 1). They reproduce by the process of "binary fission", where the duplicate cell components and divides into two cells (Figure 2). In other words, the cell divides into two without the complex movement of chromosomes seen in mitosis. New cells are produced normally become independent, but they may remain attached in linear chains or clusters grapelike. In a favorable environment, individual bacterial cells rapidly proliferate, forming colonies consisting of millions of cells.
Reproductive system of these bacteria by means of asexual (by binary fission) is the only method of reproduction among bacteria, but this only increases the amount of bacteria is not their genetic variation. Genetic variation in bacteria does not occur and performed by four methods. Three methods to get the genes from the environment or other bacteria. The fourth method is simply a mutation. This is not a method that is directed, but, by chance, mutations can be beneficial to the bacteria and the rapid generation time of bacteria (measured in minutes), beneficial mutations can quickly dominate. The first method in which genetic variation is a bacteria carried by the transformation. Transformation is a process where bacteria "take" of a gene or genes from the environment. Conjugation is the process by which a gene (on plasmid) is transferred from one bacterium to another by conjugation bridge. This transfer can be between bacteria of the same genus and species, between species in different genus or between two bacteria of different genera. Finally, transduction is the process by which genes are transferred from one bacterium to another by viruses.
Microscopic examination revealed a bacterial cell that most bacteria can be classified according to three basic shapes: bacilli (rod), coccus (spherical), and spirilla (spirals, or corkscrews). which is a composite slide which shows each of the three main types of bacteria. You need to scan the whole slide to find all three forms. It is best to use the lowest magnification microscope to look for cells initially, and then switch to the highest power to observe them in more detail. Also, consider Figure 3, which shows the differences that exist in each type of bacteria.
Most of the bacteria in this group are heterotrophic, which means that they derive their energy from organic molecules made by other organisms. Many heterotrophic bacteria is important in the ecosystem as decomposers because they feed on dead organic matter and release nutrients locked in dead tissue. In particular, they secrete enzymes that cause damage to organic materials on dead organisms and their waste, a practice that has earned them an alternative name "saprobe" (sapros from the Greek, meaning "rotten" or "fishy"). This activity is ecologically important and undoubtedly the most important of all bacterial activity. Decomposition of the release of key ions such as nitrate, phosphate, and sulfate, which then becomes available for other organisms. Other heterotrophs are parasites, often referred to as pathogens. They cause many diseases of plants and animals, including humans.
Cyanobacteria
Cyanobacteria, or most commonly known as blue-green algae. They are autotrophic, which means that they derive their energy from photosynthesis or oxidation of inorganic molecules. In addition to chlorophyll, they contain phycocyanin (blue) and phycoerythrin (red). Because of various proportions of these pigments, only about half of the actual blue-green cyanobacteria in color; many ranges in color from brown to olive green. They live in aquatic environments including oceans, ponds, lakes, tidal flats, and moist soil. Cyanobacteria exist mostly as cell colonies and filaments and sometimes as a single. Cyanobacteria can move. For example, filamentous forms such as Oscillatoria sp. screw rotates in the same way, while the form of gelatinous mucus slime slid in like that they produce. Blue-green algae produce gelatin capsule, which is lighter than water and therefore helps keep the algae near the surface of the water where there is the most sunlight.
The cells from prokaryotic cyanobacteria are quite complex (see Figure 4). Chlorophyll they are integrated into the thylakoid, the extension of the cell membrane. Actually, the whole cell photosynthesis is proportional to the eukaryotic chloroplasts. Photosynthesis in cyanobacteria is almost identical, biochemically, to that of algae and green plants. Such as algae and plants, their photosynthetic pigments including chlorophyll and accessory pigments beta-carotene, although they have no chlorophyll b. Glucose is produced by cyanobacteria in the process of photosynthesis is stored in their own form of starch, which is similar to animal glycogen. These characteristics make the precursor of cyanobacteria of eukaryotic chloroplasts.
Some cyanobacteria produce nitrogen cells called heterocysts. Their role is to combine atmospheric nitrogen into a form useful for producing amino acids and other nitrogen-containing molecules. Some cyanobacteria also produce spores (akinetes) are resistant to drying. These spores allow the cyanobacteria to survive in unfavorable environmental conditions. Anbaena sp and note (photosynthesis) vegetative cells and heterocysts (Fig. 5). Anabaena sp. has a very common feature of filamentous blue-green algae found in stagnant ponds late summer.
Eubacteria
Bacteria (singular bacterium), which includes a small group of eubacteria, relatively simple, single-celled organisms. They've been here longer and wider than other organisms. They are found in almost all habitats such as in air, water, soil, in extreme temperatures and in harsh chemical environments. Some bacteria can perform photosynthesis, using H2S instead of H2O, as the electron source, but most are heterotrophic, absorbing nutrients from the environment around him.
These bacteria are called "prokaryotes", which comes from the Greek for "prenucleus". any one characteristic that distinguishes them is that they do not contain membrane bound "organelles". Especially the genetic material they are not bound by a nuclear envelope. Bacteria do not have the chromosome, as described in the last term. Instead, their genetic material is a single circular loop of DNA (Figure 1). They reproduce by the process of "binary fission", where the duplicate cell components and divides into two cells (Figure 2). In other words, the cell divides into two without the complex movement of chromosomes seen in mitosis. New cells are produced normally become independent, but they may remain attached in linear chains or clusters grapelike. In a favorable environment, individual bacterial cells rapidly proliferate, forming colonies consisting of millions of cells.
Reproductive system of these bacteria by means of asexual (by binary fission) is the only method of reproduction among bacteria, but this only increases the amount of bacteria is not their genetic variation. Genetic variation in bacteria does not occur and performed by four methods. Three methods to get the genes from the environment or other bacteria. The fourth method is simply a mutation. This is not a method that is directed, but, by chance, mutations can be beneficial to the bacteria and the rapid generation time of bacteria (measured in minutes), beneficial mutations can quickly dominate. The first method in which genetic variation is a bacteria carried by the transformation. Transformation is a process where bacteria "take" of a gene or genes from the environment. Conjugation is the process by which a gene (on plasmid) is transferred from one bacterium to another by conjugation bridge. This transfer can be between bacteria of the same genus and species, between species in different genus or between two bacteria of different genera. Finally, transduction is the process by which genes are transferred from one bacterium to another by viruses.
Microscopic examination revealed a bacterial cell that most bacteria can be classified according to three basic shapes: bacilli (rod), coccus (spherical), and spirilla (spirals, or corkscrews). which is a composite slide which shows each of the three main types of bacteria. You need to scan the whole slide to find all three forms. It is best to use the lowest magnification microscope to look for cells initially, and then switch to the highest power to observe them in more detail. Also, consider Figure 3, which shows the differences that exist in each type of bacteria.
Most of the bacteria in this group are heterotrophic, which means that they derive their energy from organic molecules made by other organisms. Many heterotrophic bacteria is important in the ecosystem as decomposers because they feed on dead organic matter and release nutrients locked in dead tissue. In particular, they secrete enzymes that cause damage to organic materials on dead organisms and their waste, a practice that has earned them an alternative name "saprobe" (sapros from the Greek, meaning "rotten" or "fishy"). This activity is ecologically important and undoubtedly the most important of all bacterial activity. Decomposition of the release of key ions such as nitrate, phosphate, and sulfate, which then becomes available for other organisms. Other heterotrophs are parasites, often referred to as pathogens. They cause many diseases of plants and animals, including humans.
Cyanobacteria
Cyanobacteria, or most commonly known as blue-green algae. They are autotrophic, which means that they derive their energy from photosynthesis or oxidation of inorganic molecules. In addition to chlorophyll, they contain phycocyanin (blue) and phycoerythrin (red). Because of various proportions of these pigments, only about half of the actual blue-green cyanobacteria in color; many ranges in color from brown to olive green. They live in aquatic environments including oceans, ponds, lakes, tidal flats, and moist soil. Cyanobacteria exist mostly as cell colonies and filaments and sometimes as a single. Cyanobacteria can move. For example, filamentous forms such as Oscillatoria sp. screw rotates in the same way, while the form of gelatinous mucus slime slid in like that they produce. Blue-green algae produce gelatin capsule, which is lighter than water and therefore helps keep the algae near the surface of the water where there is the most sunlight.
The cells from prokaryotic cyanobacteria are quite complex (see Figure 4). Chlorophyll they are integrated into the thylakoid, the extension of the cell membrane. Actually, the whole cell photosynthesis is proportional to the eukaryotic chloroplasts. Photosynthesis in cyanobacteria is almost identical, biochemically, to that of algae and green plants. Such as algae and plants, their photosynthetic pigments including chlorophyll and accessory pigments beta-carotene, although they have no chlorophyll b. Glucose is produced by cyanobacteria in the process of photosynthesis is stored in their own form of starch, which is similar to animal glycogen. These characteristics make the precursor of cyanobacteria of eukaryotic chloroplasts.
Some cyanobacteria produce nitrogen cells called heterocysts. Their role is to combine atmospheric nitrogen into a form useful for producing amino acids and other nitrogen-containing molecules. Some cyanobacteria also produce spores (akinetes) are resistant to drying. These spores allow the cyanobacteria to survive in unfavorable environmental conditions. Anbaena sp and note (photosynthesis) vegetative cells and heterocysts (Fig. 5). Anabaena sp. has a very common feature of filamentous blue-green algae found in stagnant ponds late summer.
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