MCB 4203 Exam 1 Questions and Correct Answers Latest Update 2025 (Fully Solved)
disease - Answers damage to the host, such as that caused by an infection, which often manifests
symptoms; harm to the host that is caused by bacteria and/or the immunologic reactions to their
presence
virulence - Answers ability of a microorganism to cause disease; an organism's capacity to cause disease
virulence factor - Answers a bacterial product or strategy that contributes to the organism's ability to
survive in the host and/or cause damage to the host
Pathogenisis - Answers the origination and development of a disease; the process by which microbes
cause disease in a host
Antonievan Leeuwenhoek - Answers first microscopic observations of bacteria (17th cent.)
Pleomorphic theory of disease - Answers Antoine Béchamp; germs are a result of host disease, not the
cause.
(takeaway)
Germ theory of disease - Answers diseases are caused by living microorganisms.
Louis Pasteur - Answers processes of fermentation, food spoilage ("pasteurization"), and silkworm
disease were caused by the growth of micro-organisms; "father of germ theory of disease"; vaccination
(smallpox, anthrax)
Friedrich Henle - Answers On Miasma and Contagia- early argument for the germ theory of disease;
Robert Koch studied under his supervision in medical school
Dr. Robert Koch - Answers Improved pure-culture isolation and staining methods; animal models of
disease
Koch's first postulate - Answers the suspected pathogen must be present in all cases of the disease and
absent from healthy animals
Koch's second postulate - Answers The pathogen must be isolated from the diseased host and grown in
pure culture
Koch's third postulate - Answers The cultured microorganism should cause disease when introduced into
a healthy organism.
Koch's fourth (and 5th) postulate - Answers 4.The pathogen must be isolated from the inoculated animal
5.Pathogenic microorg. grown in pure culture and must be shown to be the original organism.
, Is Postulate #1 (Association of microbe with disease lesions) applicable to all disease-causing organisms?
- Answers Some pathogens colonize many people ('carrier-state'), but only cause disease in some;
Microbes as a risk factor for disease, rather than a cause
polymerase chain reaction (PCR) - Answers A technique for amplifying DNA in vitro by incubating with
special primers, DNA polymerase molecules, and nucleotides.
Positive control of PCR - Answers Bacterial DNA isolated from pure culture
Negative control of PCR - Answers DNA from healthy (uninfected) tissue
Immunohistochemistry - Answers localizing antigens or proteins in tissues using labeled (colored or
fluorescent) antibodies or DNA probes. +ve detection signal should be observed in diseased tissue but
not healthy tissue
Koch's postulates cannot be applied to... - Answers polymicrobial/microbiota shift diseases
molecular cloning - Answers isolation and incorporation of a piece of DNA into a vector so it can be
replicated and manipulated; new DNA inserted into the plasmid is Amplified from pathogen by PCR
Helicobacter pylori - Answers Spiral-shaped, motile, Gram-negative rod; Causative agent of duodenal
and stomach ulcers; associated with gastric cancers; colonizes 50% of pop.
Which of the following scientists was NOT a proponent of the germ theory of disease?
A) Henie
B) Koch
C) Marshall
D) Pasteur
E) Bechamp - Answers E) Bechamp
______ are produced by disease-causing bacteria and allow them to infect and survive in the host -
Answers virulence factors
Barry Marshall won the Nobel prize for his research on ___. - Answers H. pylori
Symptoms of H. pylori infection - Answers -Ache or burning pain in abdomen
-Abdominal pain that's worse when stomach is empty
-Nausea, loss of appetite
-Frequent burping, bloating, unintentional weight loss
disease - Answers damage to the host, such as that caused by an infection, which often manifests
symptoms; harm to the host that is caused by bacteria and/or the immunologic reactions to their
presence
virulence - Answers ability of a microorganism to cause disease; an organism's capacity to cause disease
virulence factor - Answers a bacterial product or strategy that contributes to the organism's ability to
survive in the host and/or cause damage to the host
Pathogenisis - Answers the origination and development of a disease; the process by which microbes
cause disease in a host
Antonievan Leeuwenhoek - Answers first microscopic observations of bacteria (17th cent.)
Pleomorphic theory of disease - Answers Antoine Béchamp; germs are a result of host disease, not the
cause.
(takeaway)
Germ theory of disease - Answers diseases are caused by living microorganisms.
Louis Pasteur - Answers processes of fermentation, food spoilage ("pasteurization"), and silkworm
disease were caused by the growth of micro-organisms; "father of germ theory of disease"; vaccination
(smallpox, anthrax)
Friedrich Henle - Answers On Miasma and Contagia- early argument for the germ theory of disease;
Robert Koch studied under his supervision in medical school
Dr. Robert Koch - Answers Improved pure-culture isolation and staining methods; animal models of
disease
Koch's first postulate - Answers the suspected pathogen must be present in all cases of the disease and
absent from healthy animals
Koch's second postulate - Answers The pathogen must be isolated from the diseased host and grown in
pure culture
Koch's third postulate - Answers The cultured microorganism should cause disease when introduced into
a healthy organism.
Koch's fourth (and 5th) postulate - Answers 4.The pathogen must be isolated from the inoculated animal
5.Pathogenic microorg. grown in pure culture and must be shown to be the original organism.
, Is Postulate #1 (Association of microbe with disease lesions) applicable to all disease-causing organisms?
- Answers Some pathogens colonize many people ('carrier-state'), but only cause disease in some;
Microbes as a risk factor for disease, rather than a cause
polymerase chain reaction (PCR) - Answers A technique for amplifying DNA in vitro by incubating with
special primers, DNA polymerase molecules, and nucleotides.
Positive control of PCR - Answers Bacterial DNA isolated from pure culture
Negative control of PCR - Answers DNA from healthy (uninfected) tissue
Immunohistochemistry - Answers localizing antigens or proteins in tissues using labeled (colored or
fluorescent) antibodies or DNA probes. +ve detection signal should be observed in diseased tissue but
not healthy tissue
Koch's postulates cannot be applied to... - Answers polymicrobial/microbiota shift diseases
molecular cloning - Answers isolation and incorporation of a piece of DNA into a vector so it can be
replicated and manipulated; new DNA inserted into the plasmid is Amplified from pathogen by PCR
Helicobacter pylori - Answers Spiral-shaped, motile, Gram-negative rod; Causative agent of duodenal
and stomach ulcers; associated with gastric cancers; colonizes 50% of pop.
Which of the following scientists was NOT a proponent of the germ theory of disease?
A) Henie
B) Koch
C) Marshall
D) Pasteur
E) Bechamp - Answers E) Bechamp
______ are produced by disease-causing bacteria and allow them to infect and survive in the host -
Answers virulence factors
Barry Marshall won the Nobel prize for his research on ___. - Answers H. pylori
Symptoms of H. pylori infection - Answers -Ache or burning pain in abdomen
-Abdominal pain that's worse when stomach is empty
-Nausea, loss of appetite
-Frequent burping, bloating, unintentional weight loss
