They consist of little more than a small piece of genetic material surrounded by a thin protein coating. Some viruses are also surrounded by a thin, fatty envelope. Viruses are different from all other infectious microorganisms because they are the only group of microorganisms that cannot replicate outside of a host cell.
Because viruses do not eat food — instead they seize materials and energy from host cells by hijacking cellular machinery — some scientists argue that they are more like complex molecules than living creatures. Viruses are known to infect nearly every type of organism on Earth. Some viruses, called bacteriophages, even infect bacteria. At Microchem Laboratory, we have made use of the physical similarity between animal viruses and certain bacteriophages to do faster, more cost-effective virucidal testing.
Simply put, certain bacteriophages are great surrogates for mammalian viruses when it comes to disinfectant testing. Bacteria are ten to times larger than viruses. They are typically 1 to 3 microns in length and take the shape of a sphere or rod. A virus is the simplest of germs—it is nothing but genetic material encased in protein.
Researchers debate whether a virus is even "alive. By itself, a virus can accomplish nothing—it needs to enter a living thing to perform its only function, which is to replicate. When a virus gets inside a human body, it can hijack a person's cellular machinery to produce clones of itself, overtaking more cells and continuing to reproduce.
When the virus reproduces faster than the immune system can control it, it begins to destroy cells and harm the body. Viruses are also the smallest germ, making them generally the easiest to contract—they're so tiny they can spread through the air in a cough or a sneeze.
Some viruses also are spread by mosquitoes or through bodily fluid. Since each virus is very different, no one drug exists to attack whichever virus is in your body. Vaccines give preemptive protection from certain viruses by training the body's immune system to recognize and attack a specific virus. Common forms: Bacteria cause food poisoning, strep throat and urinary tract infections , as well as infections such as tuberculosis.
Bacteria are bigger and more complex than viruses, though they can still spread through the air. A bacterium is a single cell, and it can live and reproduce almost anywhere on its own: in soil, in water and in our bodies.
For the most part, we live peacefully with bacteria—the colonies in our guts are helpful to us and strengthen our immune system. But like viruses, bacteria can also harm us by replicating quickly in our bodies, killing cells. Some bacteria also produce toxins which can kill cells and cause an outsized, damaging immune reaction. Broad-spectrum antibiotics were developed to kill bacteria in our bodies and in the food supply by inhibiting their growth.
But bacteria are extremely adaptive and can quickly evolve to evade antibiotics. Bacteria share their antibiotic-resistant genes with each other, meaning more strains generate resistance to the drugs we use. On the bright side though bacteria is used in making cheese, yougurt and beer, all products most people enjoy. Bacteria can come in multiple forms including cocci, bacilli, spirilla, strep, and staph. Images of each below. Viruses arfe not alive because they do not have cells, one of the essential characteristics of life.
Viruses are one of the biggest antagonists towards cells. The virus has the ability to manipulate the cell for its own use, its sits on the cell and injects its DNA into the nucleous where it starts making more viruses reproduction.
Diseases from the virus catagory can be deadly, but some are quite common including the flu, and the common cold, which can be treated with antibiotics. Protists: Protists have eukaryotic cells,and can be heterotropic but can be autotropic.
Viruses: Viruses arfe not alive because they do not have cells, one of the essential characteristics of life.
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