living microorganisms that are so small that they can be seen only with a microscope and that maintain
a more or less constant presence in a particular area
e.g. the pharynx or the rumen, includes bacteria,
viruses, protozoa, fungi.(https://medical-dictionary.thefreedictionary.com/microflora)
Microflora is the mixture of
microorganisms that are regularly founf at any anatomical site of human body.(https://www.slideshare.net/amanullah9803150/microbial-floraofthehumanbody)
In human microflora
elementry tract, urogenetal tract, ears, mouth (i.e oral cavity), nose (I.e
respiratory tract) and eyes. (https://www.slideshare.net/amanullah9803150/microbial-floraofthehumanbody)
Microflora and their benefit
The microflora of humans are extremely composite and
comprises of more than 200 species of bacteria. The physical composition of a
typical plant life gets influenced by several agents, including genetics, age,
sex, strain, nutrition and diet of the mortal.
The microflora of the digestive tract
The stomach contains fewer bacteria due to its high acidity
nature. However, there are some bacteria that survive there like the Helicobacter pylori whose human
interaction got discovered in the 1980’s and that is currently proving to be
the cause of most cases of gastritis and peptic ulcers.
Likewise, the small intestine contains small numbers of Streptococci, Lactobacilli, and yeasts, particularly Candida albicans. Nevertheless, bigger numbers of these bacteria
are found in the lower parts of the ileum, which is a section of the small
intestine before the large intestine.
The colon is the main site for bacteria in the body. Several
bacteria like Bacteroides, Bifidobacterium, Eubacterium, Coliforms
(e.g. E. coli), Streptococcus, Lactobacillus and Clostridium reside in the large intestine. Approximately twenty
percent of the faeces of an ordinary person consist of bacteria, most of which
have come from the colon.
digestive tract of herbivores:
From herbivores, we discuss cow because cow is a ruminant. Cows are not the only ruminant animals. Examples of other ruminants
are gazelles, giraffes, moose, antelope, caribou, sheep, goats, and deer. Herbivores
are animals that eat plants like kangaroos, llamas and camels have modified
stomach similar to rumens.
Rumen is a home for billions and billions of microbes that include bacteria, protists, fungi and
some viruses. Microbes of rumen are different from complex microbe organisms
that assist one another to help in the digestion of food.
Hay is eaten by ruminants like cow. It is made up of
cellulose and polymers of long molecules that the animal cannot digest. Microbes
can help in digestion of these cellulose and polymer molecules. They break down
the cellulose and polymers into small catabolic bits which the cow can digest
and absorb. Microbes play this activity by special enzymes to convert cellulose
into small digestable particles.
Microflora of the respiratory tract:
upper part of respiratory tract is a
habitat for a large number of species of bacteria so upper respiratory tract
lacks ciliated epithelium which help in cleansing action. For instance,
nostrils are a colony of enourmous number of bacteria i.e. Staphylococcus
Microbes of the Skin:
Epidermis of the skin of human is not a fertile region for
microorganisms to live because skin surface is dry and acidic upto a little
extinct while microbes require moist region for their proper growth. For instance,
Propionibacterium acne and the Staphylococcus epidermidis.
Microflora of the Nostrils:
Nostrils are moist due to the presence of mucus inside and it becomes a habitat for Gram-positive
bacteria i.e. Staphylococcus aureus. (https://www.ukessays.com/essays/biology/normal-flora-and-their-benefits.php)
There are many dissimilar types of kinship that the body can
induce with the microflora. These are:
It is a “mutual benefit”, as both organisms get benefit from
association from each other. For instance, E. coli synthesize and secrete
vitamin K and B12 which is profitable for host. In return, E. coli gets warm
& nutrient and moist rich environment for its better survival.
In this type of association, one organism gets benefit while
the other is neither benefited nor harmed. Bacteria have no commensalism
relationships with human beings. If bacteria present in our body or on the
body, they play a role which is either beneficial (antagonism of microbes) or
E. coli is present in the digestive tract of human and other
organisms where it causes no harm and consequently no disease. But when it
enters into the urogenital tract of organisms, it may be harmful (pathogenic).
aureus is a bacterium of nose microflora found in the upper portion
of respiratory tract. If it gains entry into the cells by any wound or bleeding
or burn it becomes harmful may be pathogenic. (https://www.slideshare.net/amanullah9803150/microbial-floraofthehumanbody)
Major characters of microflora are given below:
Not disease causing:
Microflora are present inside the body and also on the body.
They do not induce diseases in the healthy animals.
Very enourmous in number:
Microflora are very abundant in number. They are present in
living organisms abundantly. For example, a healthy human has about 1013 body
cells but microflora individuals are approximately 1014 in human body. One fourth
of feces contain bacteria.
Found externally to the body:
Mostly, microflora are found on external surface to the body
as on the skin, in the surroundings of eyes, in nose, in throat and also found
on internal surfaces as lower parts of
urethra and in large intestine. (https://www.ukessays.com/essays/biology/normal-flora-and-their-benefits.php)
Benefits of microflora:
Preventing colonization by microbial
anatgonism competing with nutrients and space and produce toxic condition or
environmental condition to keep harmful pathogens away (acidity in vagina).
Develop immune system by keeping it
active by providing antigens. (https://quizlet.com/7646560/normal-flora-flash-cards/)
Microflora are essential for us to survive.
They gain their food from the stuff in our pie hole.
If colonies of bacteria are worn out by poisons or
antibiotics, they must be replaced otherwise we would die ultimately. (https://www.quora.com/What-are-the-benefits-of-normal-flora)
They provide a host defence mechanism by taking control on ecological
niches for bacteria, e.g. the intestinal villi.
Bacteria produce and excrete various compounds like vitamin B12 and
vitamin K in the intestine which are important nutrients for host.
The oral microflora assist in immunity through inducing low level of
circulating and secretory antibiotics that kill pathogens. In other words, they
enhance body’s immunity.
The oral bacterial flora kill nonindigenous species by producing
inhibitory fatty acids, peroxides and bacteriocins (it is a protein and bacreria produce it,
it helps in stamping and killing microbes).
Microflora help to digest food as they break down
foodstuffs that are normally indigestible by the host into forms that are
easily digestible by the hosts.
The Microflora protects the host from infection by harmful pathogenic organisms.
They produce antibacterial substances as by product of
metabolism, so they have a local antibiotic effect which retard the attack of
invaders on host.
They stimulate an immunological response (an
antibody-mediated immune response) as they act as antigens in the human body. (https://www.ukessays.com/essays/biology/normal-flora-and-their-benefits.php)
Disadvantages of microflora:
Microflora is harmful when overgrown (i.e. use of antibiotics) and
misplaced (i.e. urinary tract flora may placed with facel flora). (https://quizlet.com/7646560/normal-flora-flash-cards/)
Microflora may also cause disease in following conditions:
If individual become immunocompromised.
If he change his anatomical location as usual.
There are few limitations of microflora to the human body as
well. For example, most of the microflora are pathogens and may cause
infectious diseases. Similarly, if microflora take control on certain tissues,
they can cause infection as well as destruction. Likewise, the Microbe may
absorb some of the hosts nutrients due to competition, leading to the
development of bacterial antibiotic resistance in humans. (https://www.ukessays.com/essays/biology/normal-flora-and-their-benefits.php)