Human-Microbe Relationships Flashcards
what is Symbiosis & Categories of symbiosis?
– Relationship of the human host and the
indigenous flora
. Categories of symbiosis
– Mutualism
– Commensalism
– Parasitism
What is Mutualism & its sub-catagories?
– Both organisms benefit and depend on each other
. Synergism
- Two organisms work together to accomplish a goal they could not do independently
Examples of Mutualism:
. Escherichia coli, which colonizes w/in the human intestine, obtains nutrients from the food that humans eat.
. E.coli produces vitamin K, which is essential to the blood-clotting process in human
Examples of Synergism:
. Fusobacteria & Spirochetes work together to cause a disease known as trench mouth
What is Commensalism & its other categories?
– One organism benefits
– The second neither benefits or is harmed
. Neutralism
- Two organism occupy the same area with no effect on each other
. Antagonism
- One microorganism inhibits or interferes the growth of another
Example of Commensalism:
. Indigenous Microflora on the skin of humans obtain nutrients, but do not affect the skin or human body. To a certain extent they benefit humans by occupying space and preventing other potentially harmful microbes from colonizing, a process referred to as competitive exclusion
Example of Antagonism:
. A microbe produces waste products that are toxic to the microbes nearby
What is Parasitism?
– One organism benefits and the host is harmed
Example of Parasitism:
. Endoparasites, such as intestinal worms, cause an infection & deplete the body of nutrition.
Microorganisms that cause an infection are called Pathogens
Which is another subcategory of Parasitism
Examples of pathogenic relationships:
. Commensal microbes: that becomes opportunistic by entering through a surgical skin incision
. Nosocomial infections: (acquired in healthcare setting) such as urinary tract infection. 25% acquired during surgery
. Airborne viruses: such as the virus that causes the common cold
