Duringtheirlaboratorytesting,ifdisinfectantsarecarriedoverinto microbial cultures, could the results be affected? Explain. Definedisinfection.Howdoesitdifferfromantisepsis?...

Running head: THE WORLD OF MICROBES
The World of Microbes


During their laboratory testing, if disinfectants are carried over into microbial cultures,
could the results be affected? Explain.
Answer
Definitely results may be affected as; disinfectants would kill microbes. (Allen, 1998)
Define disinfection.
Answer
Disinfectants are the chemicals (such as; sodium hypochlorite) which may interrupt the
considerable cellular constituents or procedures with the intention of elimination of
microorganisms and this process of destruction by disinfectants is known as; disinfection.
(Collins, 1986)
How does it differ from antisepsis?
Answer
Disinfection may destruct all microbes excluding endospores and viruses. On the other hand,
Antisepsis means, the disinfection of living tissues for instance; human skin and, especially,
wounds. (Collins, 1976)
What does bactericidal mean?
Answer
The agents which are capable to kill bacterium are known as; bactericidal. (Griffiths et al.1999)
http://www.mansfield.ohio-state.edu/~sabedon/biol2030.htm#disinfection
The World of Microbes


Bacteriostatic?
Answer
Agents which can prevent bacterial growth as well as their multiplication only rather than killing
them are termed as bacteriostatic. (Hegna, 1977)
Virucidal?
Answer
The agents which can kill virus are called virucidal. (Ortalo-Magne, 1955)
Fungi static?
Answer
Agents which can stop fungal growth and multiplication are called fungi static. (Allen, 1998)
Why are control cultures necessary in evaluating disinfectants?
Answer
It is used for the purpose of comparative analysis as; a control plate is not exposed to a
disinfectant hence; it should reflect more colonies in compare to the plates that have been
exposed to a disinfectant. Now, according to the quality of disinfectant, the difference (in terms
of colonies) between a control plate and an exposed plate might be increased. (Collins, 1986)
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What can influence the activity of a disinfectant?
Answer
The activity of a disinfectant may get influenced via various factors such as;
1. Number and Location of Microorganisms
2. Innate Resistance of Microorganisms
3. Concentration and Potency of Disinfectants
4. Temperature, pH, relative humidity, and water hardness
5. Organic and Inorganic Matter
6. Duration of Exposure
7. Biofilms etc. (Allen, 1998)
Why do microorganisms differ in their response to disinfectants?
Answer
Microbial response towards disinfectant may depend on various characteristics of them for
example; few microbes have capability to produce spores which are resistant to disinfectants
because of presence of spore coat and cortex that can work as a barrier. Besides, mycobacteria
consist of waxy cell wall hence; can prevent entry of disinfectant. In the same way, gram-
negative bacteria’s outer membrane might also perform the role of barrier against the uptake of
disinfectants. (Collins, 1986)
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What microorganisms are most susceptible to disinfectants?
Answer
Actively growing microbes and microbes that are devoid of endospores can be termed as most
susceptible to disinfectants. (Allen, 1998)
Which microbial forms are most resistant to disinfectants?
Answer
Except for prions, bacterial spores are able to reflect the highest intrinsic resistance to chemical
germicides. After these, coccidia (e.g., Cryptosporidium) might be termed as quite resistant.
(Griffiths et al.1999)
How can bacteriostatic and bactericidal disinfectants be distinguished?
Answer
Bactericidal disinfectants are able to...