What are 3 examples of helpful bacteria and 3 examples of harmful bacteria?

Some examples of helpful bacteria include E. Coli (when used for the digestion process), Streptomyces, and Rhizobium. Some examples of harmful bacteria include E. Coli (when contaminating food), Listeriosis, and Salmonella.

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Helpful bacteria:

  • E. Coli are found in the intestines of humans and aid in digestion.
  • Streptomyces is used in making antibiotics.
  • Rhizobium are helpful bacteria found in the soil. They convert nitrogen in the soil.

Harmful bacteria:

  • E. Coli can also be harmful if food or water is contaminated with it and then eaten.
  • Listeriosis can cause individuals to become very ill and can even be potentially deadly. Examples of where it can be found are in shellfish, cold cuts, and unpasteurized milk.
  • Salmonella is very dangerous and lives in the intestinal tracts of humans . It is spread via feces. Foods like poultry and eggs can be contaminated with salmonella and cause severe diarrhea.

The human body contains numerous types of bacteria that are very beneficial and actually protect us from the harmful bacteria.

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parama9000 | Student

E. Coli can be helpful when it aids in the digestion of food but harmful when it contaminates food or water.

Lactobactillus aids in digestion as well

Penicillin was used in the production of antibiotics.

There are many more harmful bacteria out there then good. Thoat infections, for example, are caused by bacteria.

jess1999 | Student

Examples of helpful bacteria :

  • Lactobacillus : lives in intestines where it helps with digestion
  • E.Coli : can prevent and treat ulcerative colitis
  • Streptomyces : they are used in making antibiotics.

Examples of harmful bacteria

  • Clostridia: can infect wounds or cause illness
  • Streptococci : cause strep throat, pneumonia, and other illness
  • Staphylococci : cause skin infection and infections in bones




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krishna-agrawala | Student

Bacteria are very small single cell orgasms. They are among the smallest living beings measuring from 0.3 to 2.0 microns in diameter. Some scientists classify bacteria as plants while others classify in a separate group of living beings which are neither plant of animal.

There are thousands of different kind of bacterias. Most of these varieties are harmless to human beings. Some varieties are harmful, while still others are helpful to humans. The common varieties of bacteria that are useful to humans include various types of antibiotics. Some bacterias that live in human intestine help in digestion. Other bacteria in human intestine produce some vitamins. The process of fermentation used for wine making, cheese processing, and many other food, relies on use of specific bacteria.

Harmful bacteria can cause diseases such as cholera, leprosy, tuberculosis and typhoid. Other bacteria produce toxins which cause diseases such as diphtheria, scarlet fever and tetanus. A form of bacteria that develops in preserved food produces toxins that cause form of food poisoning called botulism.

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