Types of phatogen

Types of phatogen



Many of the most common diseases are caused by tiny microorganisms called PATHOGEN. Pathogen infects, or invades the body and attacks its cells and tissues. Some bacteria, rickettsias, fungi, protozoans, certain types of worms, and all viruses are pathogens. Diseases caused by the direct or indirect spread of pathogens from one person to another are called communicable diseases.


I read that BACTERIA are one-celled microscopic organisms that rank among the most widespread of living things. Some are small that a single grain of soil may contain over 100 million of them. Most bacteria do not cause disease. In order to live, all bacteria must have a food supply, as well as suitable temperature, moisture and darkness. Some bacteria digest nonliving food materials such as milk and meat. These organisms are called saprophytes. If the food supply is a living plant or animal, the microorganism is called a parasite. The plant or animal that the parasite feeds on is called a host.


Toxin Bacteria produces a certain poison. Botulism is a food poison. These bacteria live in the soil. Once they enter the body through a wound, they can cause tetanus or lockjaw. Other bacteria cause pneumonia.


It lives in the human mouth and intestines and on our skin. These help protect us from harmful bacteria. Lactobacili, found in the gastro-intestinal tract, produce lactic acid from simple carbohydrates. Coliform bacilli, found in the intestines, help break down carbohydrates and combat disease-causing bacteria. Resident bacteria cause infections when it moves from where residents are. Example, a bacteria in the mouth is moved to the ear then you get an infected ear.


These are organisms that are considered intermediate, that is,
somewhere between a virus and a bacterium. Most of them grow in the intestinal tracts of insects, which carry them to their...

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