MCB 100 Exam 3 UPDATED ACTUAL Questions And Correct Answers
C
Terms in this set (214)
Amensalism Both host and microbe co-inhabit with harm to one (usually the host) but no
apparent benefit or harm to the other
Commensalism Both host and microbe co-inhabit with benefit to one (usually the microbe) but no
apparent benefit or harm to the other (usually the host)
Resident microbes: type of host-microbe relationship For microbes that reside in the body - once considered commensalism but
perhaps better described as either mutualism or parasitism; many resident
microbes are not as harmless as once believed and are maybe just being
controlled/contained by the immune system
Parasitism Many microbes are or may become pathogens
Colonization Occupation, growth, and multiplication of microorganisms in the host
Infection Colonization by microbes that can damage cells or tissues of the body
Symptoms Effects of infection that are apparent to the host, but hard to quantify
Signs Effects of infection that can be measured by physical methods
Disease Infection that produces damage to the body, with or without symptoms (due to
damage)
Pathogen Any microbe that causes disease
Opportunistic pathogens Commensals that can cause disease under certain conditions where normal
barriers of the host are breached or where host defenses are compromised
Commensal - pathogen relationship Many commensals start out as pathogens, but once the host immune system
controls them, they no longer cause disease
Virulence/pathogenicity Ability of a pathogen to cause infection and disease
Virulence factors Microbial products or strategies that are used by the pathogen that contribute to
virulence
Typical stages of disease progression 1. Establishment of infection; 2. Incubation period before symptoms manifest; 3.
Acute period; 4. Decline period; 5. Convalescence period
, (Stages of disease progression) Establishment of infection 1. Attachment - adherence to host cells
2. Colonization and growth of microbe
(Stages of disease progression) Incubation period before 1. Evasion of host immune system - innate immune system responds, but is
symptoms manifest overcome
2. Invasion and/or production of toxic substances - damage to host that manifests
in disease (often with symptoms and signs of disease)
(Stages of disease progression) Acute period 1. Dissemination in body - spread to other body sites
2. Disease signs and symptoms evident to host - Prodromal Period (not in all
cases), followed by Overt Illness
3. Transmission - spread to external environment and/or other hosts
(Stages of disease progression) Decline period 1. Immunity - host adaptive immune system responds
2. Disease signs and symptoms subside
(Stages of disease progression) Convalescence period 1. Host immune system is fully functional and protective
2. Host regains strength and returns to normal
Predisposing conditions that affect host susceptibility - 1. Age - usually young or old are most susceptible due to lower immune status
not just the microbe 2. Other diseases - co-infection or prior infection with other pathogens (ex: HIV or
mycoplasma) or diseases (ex: cancer, heart disease, stroke, obesity, dementia) that
affect defenses of the human body
3. Nutritional status - malnutrition affects defenses of the body
4. Stress/lifestyle - emotional or physical stress (ex: smoking, drinking) affects
defenses of the body sites
Predisposing conditions that affect host susceptibility - 5. Antibiotic use - affects normal "protective" microbiota of the body and causes
not just the microbe CONT shift in microbial growth patterns
6. Surgery/injury - breach of natural protective barriers
7. Exposure - increased transmission rate (ex: crowds, sexual practices, poor
sanitation, pesticides/herbicides, pollution)
8. Vaccination status - prior immunization provides more rapid protective immune
response upon exposure
9. Genetic differences - host genetic background can make host more or less
susceptible to infection (ex: mutations that make some people more resistant to
HIV)
Koch's Postulates A set of 4 rules that must be satisfied to link a potential pathogen to a particular
disease
To establish that a particular microbe is the cause 1. Found in all cases where symptoms/signs of the disease are evident, while
(etiology) of disease, it must be: absent in healthy individuals without disease
2. Isolated from the site of infection and maintained in a pure culture
3. Capable of reproducing the disease when the cultured isolate is inoculated into
a susceptible host
4. Retrievable from an experimentally inoculated host and cultured again from the
experimentally infected host
Problem satisfying Koch's Postulates There are some infectious microbes for which Koch's Postulates have not been
satisfied, yet there is general agreement that a specific microbe causes the
infections
C
Terms in this set (214)
Amensalism Both host and microbe co-inhabit with harm to one (usually the host) but no
apparent benefit or harm to the other
Commensalism Both host and microbe co-inhabit with benefit to one (usually the microbe) but no
apparent benefit or harm to the other (usually the host)
Resident microbes: type of host-microbe relationship For microbes that reside in the body - once considered commensalism but
perhaps better described as either mutualism or parasitism; many resident
microbes are not as harmless as once believed and are maybe just being
controlled/contained by the immune system
Parasitism Many microbes are or may become pathogens
Colonization Occupation, growth, and multiplication of microorganisms in the host
Infection Colonization by microbes that can damage cells or tissues of the body
Symptoms Effects of infection that are apparent to the host, but hard to quantify
Signs Effects of infection that can be measured by physical methods
Disease Infection that produces damage to the body, with or without symptoms (due to
damage)
Pathogen Any microbe that causes disease
Opportunistic pathogens Commensals that can cause disease under certain conditions where normal
barriers of the host are breached or where host defenses are compromised
Commensal - pathogen relationship Many commensals start out as pathogens, but once the host immune system
controls them, they no longer cause disease
Virulence/pathogenicity Ability of a pathogen to cause infection and disease
Virulence factors Microbial products or strategies that are used by the pathogen that contribute to
virulence
Typical stages of disease progression 1. Establishment of infection; 2. Incubation period before symptoms manifest; 3.
Acute period; 4. Decline period; 5. Convalescence period
, (Stages of disease progression) Establishment of infection 1. Attachment - adherence to host cells
2. Colonization and growth of microbe
(Stages of disease progression) Incubation period before 1. Evasion of host immune system - innate immune system responds, but is
symptoms manifest overcome
2. Invasion and/or production of toxic substances - damage to host that manifests
in disease (often with symptoms and signs of disease)
(Stages of disease progression) Acute period 1. Dissemination in body - spread to other body sites
2. Disease signs and symptoms evident to host - Prodromal Period (not in all
cases), followed by Overt Illness
3. Transmission - spread to external environment and/or other hosts
(Stages of disease progression) Decline period 1. Immunity - host adaptive immune system responds
2. Disease signs and symptoms subside
(Stages of disease progression) Convalescence period 1. Host immune system is fully functional and protective
2. Host regains strength and returns to normal
Predisposing conditions that affect host susceptibility - 1. Age - usually young or old are most susceptible due to lower immune status
not just the microbe 2. Other diseases - co-infection or prior infection with other pathogens (ex: HIV or
mycoplasma) or diseases (ex: cancer, heart disease, stroke, obesity, dementia) that
affect defenses of the human body
3. Nutritional status - malnutrition affects defenses of the body
4. Stress/lifestyle - emotional or physical stress (ex: smoking, drinking) affects
defenses of the body sites
Predisposing conditions that affect host susceptibility - 5. Antibiotic use - affects normal "protective" microbiota of the body and causes
not just the microbe CONT shift in microbial growth patterns
6. Surgery/injury - breach of natural protective barriers
7. Exposure - increased transmission rate (ex: crowds, sexual practices, poor
sanitation, pesticides/herbicides, pollution)
8. Vaccination status - prior immunization provides more rapid protective immune
response upon exposure
9. Genetic differences - host genetic background can make host more or less
susceptible to infection (ex: mutations that make some people more resistant to
HIV)
Koch's Postulates A set of 4 rules that must be satisfied to link a potential pathogen to a particular
disease
To establish that a particular microbe is the cause 1. Found in all cases where symptoms/signs of the disease are evident, while
(etiology) of disease, it must be: absent in healthy individuals without disease
2. Isolated from the site of infection and maintained in a pure culture
3. Capable of reproducing the disease when the cultured isolate is inoculated into
a susceptible host
4. Retrievable from an experimentally inoculated host and cultured again from the
experimentally infected host
Problem satisfying Koch's Postulates There are some infectious microbes for which Koch's Postulates have not been
satisfied, yet there is general agreement that a specific microbe causes the
infections
