Diversity of Living Things

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BACTERIA.
CLASSIFICATION

Bacteria are extremely small and some can be just seen with the naked human eye. They are much smaller than eukaryotic cells but are still very complex despite their size. .the cell is surrounded by a cell membrane that enclosees the bacteria cell. They are single celled organisms. Bacteria are prokaryotic cells and therefore do not have a nucleus and do not have a lot of organelles like: mitochondria, chloroplasts, and other organelles that are usually found in eukaryotic cells.. They reproduce asexually and mutations occur very rapidly. The main shapes of bacteria are cocci: oval shaped, bacilli- rod shaped and spirilli- spiral shaped. Bacteria can use almost any source as their energy source. This is why they are found everywhere and can survive in so many different environments. Bacteria are very useful but some can be dangerous. Bacteria do jobs that no other kingdom can do and they are often the most important jobs that benefit us the most. Which range from recycling dead organisms to helping cows digest cellulose. Some dangerous forms of bacteria can cause deadly diseases like salmonella, a food poisoning that is very deadly. There are some major phlyuhs Chlorobia-and cyanobacteria are shaped like rods, spirals and are anaerobic. They do contain chloryphyll and can produce their own food through photosynthesis. Not all have to use sunlight to induce that process. Cyanobacteria give out oxygen. Proteobacteria- These live on the roots of some platns and transfer nitrogen from the air to the soil. This phylum contain bavteria like salmonella and E. Coli which are very dangerous, but most others are harmless. Firmicutes- contains a wide variety of bacteria that has really thick cell walls. This contains the bacteria Bacillus anthracis causing anthrax. Acquificae- are bacteria that live in more extreme environments. They are autotrophs They make their food by breaking down chemicals through the process chemosynthesis. Therefore can survive in extreme environments other organisms can’t. Bacteroids- are rod shaped bacteria that live in most mammals digestive tracts, break down molecules and can keep harmful bacteria from living inside us.

Structure
Bacteria are fairly simple considering that they have one nucleus, no specialized structures and have many flagella for movement.Classifying the bacteria can be easily done simply by its shape. Bacteria also can arrange differently and can be recognized with the prefixes that go before their names. Diplo- are bacteria that arrange in pairs.

Staphylo- are bacteria that arrange in clusters.
Strepto- are ones that arrange in chains.
Along with the arrangements are the shape of the bacteria itself. Cocci- are round of pherical bacteria. Arrange in chains, tetrads, cubes of eight of in random clusters. An example is S.pneumoniae. Bacilli- are rod shaped bacteria. They can arrange as single bacteria, in pairs, in chains or in an oval. Example is moraxella catarrhalis. They have more surface area to absorb more nutrients. Spirilli- that come in three forms vibrio(shaped like a comma). Spirillum( thick spiral shape). Spirochete ( thin flexible spirals) Capsule- some bacteria have a polysaccharide covered capsule, that can prevent the bacteria from being engulfed and from drying out. This is usually found in the more deadly disease causing bacteria. Cell wall- the cell wall is made of peptidoglycan a protein sugar. It protects the bacteria and can keep it from collapsing when exposed to pressure. The two major differences are gram positive and gram negative cell wall, depending on its thickness. Cytoplasm- where the functions of growth, metabolism. Made of water, emzymes, nutrients and waste. It also contains the chromosome, which is a single continuous strand of DNA that is not contained by a nucleus. Plasmids- conatin genetic instructions for carrying out binary fission. They are not essential for bacteris but they do give them a...
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