MICROBIOLOGY LAB FINAL EXAM HCC HAROLD KAY
Why do we culture bacteria ? - Answers :To isolate , identify and study microorganisms
What do you understand by opportunistic pathogens ? - Answers :Normal inhabitants of
the human body that are non pathogenic but become pathogenic but become
pathogenic when immune system is compromised
What is normal flora? - Answers :The native microbial forms that an individual harbors.
Non pathogenic
Give three examples of opportunistic pathogen's - Answers :Candida albicans,
Pseudonomas aeruginosa, staphylococcus aureus
Examples of true pathogens - Answers :Influenza virus, plague bacillus and malaria
protozoan
Know four pathogenic viruses and diseases they cause in humans - Answers :Human
papilloma virus - cervical cancer
Human immunodeficiency virus - acquired immunodeficiency syndrome
Hepatitis C - liver cancer
Norwalk virus - acute gastroenteritis
What is lysogeny ? - Answers :Indefinite persistence of bacteriophage DNA in a host
without bringing about the production of virions
Stages of lysogeny - Answers :Attachment (adsorption) , entry (penetration) , uncoat (no
uncoat in bacteriophage of animal host cells) and integration
Know the three modes/types of genetic transfer between bacteria - Answers
:Transformation- when bacteria assimilates genetic material from its environment
(indirect contact )
Transduction- when bacteria transfers genetic materials through a bacteriophage (direct
contact)
Conjugation - when bacteria transfers genetic material through sex pilli ( direct contact )
What are bacteriophages ? - Answers :Bacteria that is infected by a virus
What is the lytic cycle ? - Answers :Death and deterioration of Host cell
, Stages of lytic cycle - Answers :Adsorption - binding of virus to specific molecule on
host cell
Penetration- genome enters host cell
Uncoating - viral nuclear acid is released from the capsid , exposes it's genome
Synthesis - viral components are produced , viral genome integrates with the host cell
genome
Assembly - new viral particles are constructed
Release - assembled viruses are released by Budding or cell lysis
Why do we sterilize in microbiology ? - Answers :To destroy or remove all viable
organisms including viruses. To avoid contamination.
Types of staining procedure - Answers :Simple stain , negative stain , gram stain, acid
fast stain
List two bacteria that are hemolytic(break down blood) and the disease they cause -
Answers :Streptococcus pneumoniae - meningitis
Streptococcus agalacti ae - chorioamnionitis(breaks down blood in newborns)
What is miniaturized or automated bacteria identification ? - Answers :Biolog micro
station - a computer used for identification of microbes
Advantages include time , accuracy and efficiency
Types of hemolysis - Answers :Alpha-partial/incomplete hemolysis-green to brown. ,
beta-complete breakdown of blood cells-clear. and gamma-none-white/cloudy
What is an enriched medium ? - Answers :Contains complex organic substances such
as blood , serum , hemoglobin or special growth factors require by fastidious microbes
Ex. Blood agar
Know species and genus of bacteria in the family enterobacteriaceae - Answers :E. coli
, Salmonella, Yersinia pestis
What is selective media ? - Answers :Contains one or more agents that inhibit growth of
some microbes and encourage growth of the desired microbes
What is differential media? - Answers :Allows growth of several types of microbes and
displays visible differences among those microbes
Why do we culture bacteria ? - Answers :To isolate , identify and study microorganisms
What do you understand by opportunistic pathogens ? - Answers :Normal inhabitants of
the human body that are non pathogenic but become pathogenic but become
pathogenic when immune system is compromised
What is normal flora? - Answers :The native microbial forms that an individual harbors.
Non pathogenic
Give three examples of opportunistic pathogen's - Answers :Candida albicans,
Pseudonomas aeruginosa, staphylococcus aureus
Examples of true pathogens - Answers :Influenza virus, plague bacillus and malaria
protozoan
Know four pathogenic viruses and diseases they cause in humans - Answers :Human
papilloma virus - cervical cancer
Human immunodeficiency virus - acquired immunodeficiency syndrome
Hepatitis C - liver cancer
Norwalk virus - acute gastroenteritis
What is lysogeny ? - Answers :Indefinite persistence of bacteriophage DNA in a host
without bringing about the production of virions
Stages of lysogeny - Answers :Attachment (adsorption) , entry (penetration) , uncoat (no
uncoat in bacteriophage of animal host cells) and integration
Know the three modes/types of genetic transfer between bacteria - Answers
:Transformation- when bacteria assimilates genetic material from its environment
(indirect contact )
Transduction- when bacteria transfers genetic materials through a bacteriophage (direct
contact)
Conjugation - when bacteria transfers genetic material through sex pilli ( direct contact )
What are bacteriophages ? - Answers :Bacteria that is infected by a virus
What is the lytic cycle ? - Answers :Death and deterioration of Host cell
, Stages of lytic cycle - Answers :Adsorption - binding of virus to specific molecule on
host cell
Penetration- genome enters host cell
Uncoating - viral nuclear acid is released from the capsid , exposes it's genome
Synthesis - viral components are produced , viral genome integrates with the host cell
genome
Assembly - new viral particles are constructed
Release - assembled viruses are released by Budding or cell lysis
Why do we sterilize in microbiology ? - Answers :To destroy or remove all viable
organisms including viruses. To avoid contamination.
Types of staining procedure - Answers :Simple stain , negative stain , gram stain, acid
fast stain
List two bacteria that are hemolytic(break down blood) and the disease they cause -
Answers :Streptococcus pneumoniae - meningitis
Streptococcus agalacti ae - chorioamnionitis(breaks down blood in newborns)
What is miniaturized or automated bacteria identification ? - Answers :Biolog micro
station - a computer used for identification of microbes
Advantages include time , accuracy and efficiency
Types of hemolysis - Answers :Alpha-partial/incomplete hemolysis-green to brown. ,
beta-complete breakdown of blood cells-clear. and gamma-none-white/cloudy
What is an enriched medium ? - Answers :Contains complex organic substances such
as blood , serum , hemoglobin or special growth factors require by fastidious microbes
Ex. Blood agar
Know species and genus of bacteria in the family enterobacteriaceae - Answers :E. coli
, Salmonella, Yersinia pestis
What is selective media ? - Answers :Contains one or more agents that inhibit growth of
some microbes and encourage growth of the desired microbes
What is differential media? - Answers :Allows growth of several types of microbes and
displays visible differences among those microbes
