Microbiology Final

All that is supposed to be in the final

Infection definition

colonization of the body by pathogens

Disease definition

an abnormal state when body is not functioning normally

What is a pathogen

a disease causing organism

Pathogenicity definition

a measurement of an organism’s potential to cause disease

Virulence definition

the degree of pathogenicity of an organism

What are normal microbiota

organisms that establish permanent residence but dont produce disease under normal body conditions

What are normal microbiota regions based on

nutrients, physical, chemical, and mechanical factors, and defenses of the host

Where do babies gain their microbiomes

in utero, birth, milk, caregivers, and the environment

How is a microbiome acquired in utero

the mother’s womb has her own microbiome

How is a microbiome acquired during birth

primarily by coming into contact with the mother's bacteria as it passes through the birth canal. For babies born via C-section, the initial microbiome comes more from the hospital environment and the mother's skin, which are different from the vaginal microbiota

How is a microbiome acquired by breast milk, compare it to formula

breast milk has a microbiome, but sterilized baby formula has none

How is a microbiome acquired from caregivers

family, siblings, and others share microbes with the baby

How is a microbiome acquired from the environment

baby can pick up microbes from anything it comes in contact with

Why would a doctor smear cesarean babies with vaginal canal bacteria?

because the baby did not pass through, missing the bacteria that could help shape its microbiome

Probiotics definition

live microbial cultures used to exert benefits to the host

What are opportunistic pathogens

under normal conditions they do not cause disease, but in a changed environment can cause disease

How do microbes cause disease

find a portal of entry, attaching firmly and negotiating the microbiome, surviving host defenses, causing damage/disease, exiting host

What is the first step in how microbes cause disease

gain entrance through a portal of entry

What are common portals of entry

skin, gastrointestinal tract, respiratory tract, urogenital tract

What is significant about the number of microbes in a disease

the likelihood of disease increases as the number of pathogens increases

ID50

the infection dose for 50 percent of population, how much needed to infect 50 percent of population

The lower the number, the more _____ the organism

virulent

LD50

the lethal dose for 50 percent of population

A bioweapon would need to be very ____

virulent

What is the second step in how microbes cause diease

adhere to host tissue

What are the ways a microbe adheres to host tissue

most methods are structures, some examples are fimbriae, hook/spirochete, and capsule

What is the third step in how a microbe causes disease

survives defenses, by producing antiphagocytic factors, means not going to be destroying

What are some ways microbes survive defenses

produce leukocidins (toxic to white blood cells), secrete slime layer or capsule to inhibit engulfing, survive inside phagocytes, and antigenic variation

What is antigenic variation

antigens on the surface of the microbe change enough that the immune system cannot recognize anymore, how we get new flu shots each year

What is the fourth step in how microbes cause disease

it actually causes disease/damage

How do microbes actually cause disease

microbes secrete enzymes and toxins, exoenzymes are produces by pathogens to break down tissues

What are the two types of toxins produces by microbes to cause disease

exotoxins and endotoxins, usually not both produced together

Exotoxin characeristics

most are enzymes, small amounts cause great harm, most come from gram positive only a few from gram negative, genes travel on plasmids then share them, soluble in body fluids, so easy to move through the body

Exotoxins definition

toxic substances released outside cell

What is the importance of circulatory and lymphatic systems?

route for returning fluid to circulatory system, drain off system for inflammatory response, provide surveillance, recognition, and protection

What are the goals of the immune system?

determine self from nonself and destroy invaders

What are the physical and anatomical barriers

skin, mucus, tears, earwax, and stomach acid

What is non-specific (innate) immunity

general ability of certain cells to inhibit pathogenic organisms

What are factors of innate immunity

natural host resistance, age, stress, diet, tissue specificity, and normal microbiota

An endotoxin is ________.

• indicative of a fungal infection

• indicative of gram-positive organisms

• indicative of viral infections

• secreted by pathogenic organisms

• indicative of gram-negative organisms

indicative of gram-negative organisms

Which factor might determine if you get sick from an infection when someone else might not?

• whether the microbe is gram-negative or gram-positive

• your general health

• your astrological sign

• your weight

your general health

Normal biota includes each of the following except ______.

• viruses

• protozoans

• bacteria

• fungi

all of choices are correct

The term infection refers to_______.

• microorganisms colonizing the body

• contact with microorganisms

• pathogens penetrating host defenses

• contact with pathogens

• none of these are correct

pathogens penetrating host defenses

The subjective evidence of disease sensed by the patient is termed an _____.

• inflammation

• pathology

• syndrome

• sign

• symptom

symptom

An inanimate object that harbors and transmits a pathogen is a _____.

fomite

Which of the following are virulence factors?

• toxins

• capsules

• enzymes

• all are correct

all are correct

Opportunistic pathogens ______.

• have well-developed virulence factors

• are always pathogens

• cause disease in every individual

• cause disease in compromised individuals

• none are correct

cause disease in compromised individuals

Most microbial exotoxins would be created using the process of _______. 

• mutation

• transcription and translation

• fatty acid synthesis

• DNA replication

When the resident microbiota prevents the establishment of a pathogen, it is called _____.

• disruption

• a superinfection

• microbial antagonism

• a nonliving reservoir

microbial antagonism

NCLEX: Clinical Application

An RN working in the labor and delivery unit of a hospital is caring for a mother in labor following pre-mature rupture of membranes. The mother is known to be a Hepatitis B carrier based on prenatal testing. The course of her labor has been prolonged but is now progressing rapidly. The RN prepares to assist with delivery.

Which of the following is the first exposure of the infant to environmental microbes?

• contact with healthcare workers

• breastfeeding

• passage through vaginal canal

• in utero

passage through vaginal canal

NCLEX: Clinical Application

An RN working in the labor and delivery unit of a hospital is caring for a mother in labor following pre-mature rupture of membranes. The mother is known to be a Hepatitis B carrier based on prenatal testing. The course of her labor has been prolonged but is now progressing rapidly. The RN prepares to assist with delivery.

The mother displays no evidence of active Hepatitis B disease and her carrier status was discovered with routine prenatal screening, Which term best describes her carrier status?

• asymptomatic carrier

• incubating carrier

• passive carrier

• convalescent carrier

asymptomatic carrier

NCLEX: Clinical Application

An RN working in the labor and delivery unit of a hospital is caring for a mother in labor following pre-mature rupture of membranes. The mother is known to be a Hepatitis B carrier based on prenatal testing. The course of her labor has been prolonged but is now progressing rapidly. The RN prepares to assist with delivery.

If an infant is exposed to Hepatitis B during delivery, which term best describes the pattern of transmission?

• vertical transmission

• horizontal transmission

• vector transmission

• indirect transmission

vertical transmission

An outbreak of staphylococcal food poisoning among individuals who attended a family reunion and ate the potato salad.

point source epidemic

The persistent cholera epidemic studied by John Snow in London during the mid-1050s, during which he traced the source to a sewage-contaminated community pump.

common source epidemic

An outbreak of measles among unvaccinated children in a large Amish community

propagated epidemic

Order the four stages in the course of an infection

1. prodromal stage

2. incubation period

3. convalescent period

4. acute phase

2, 1, 4, 3

Which of the following may be the result of colonization with a pathogenic microbe?

Check All That Apply

1. The pathogen does not attach to the host well and is cleared by the host.

2. The pathogen may multiply and cause infection, leading to possible disease.

3. The pathogen may reside as part of the resident microbiota in low numbers.

4. The pathogen must be cleared entirely from the body or it will lead to disease.

5. The presence of the pathogen will result in signs and symptoms that can be clinically diagnosed.

1, 2, 3

Which of the following may be members of the holobiont

• resident microbes

• pathogens

• transient microbes

• all

all

T/F

you may not always know you have been colonized by a microbe, but you will always know if it process to an infection

Media

material prepared for the growth of microbes

Culture

microbes that grow in or on a medium

Agar

solidifying agent used in media

Chemically defined media

exact chemical composition

Complex media

general media, used to grow many bacteria

Reducing media

media for anaerobes, contains materials that depletes the oxygen level

Enrichment media

provides nutrients and conditions to increase growth to detectable levels

Selective media

encourages growth of one microbe and suppress growth of others

Differential media

used to differentiate different types while on the same plate

cells that lack internal membranes and organelles, do not specialize, and do not build multicellular organisms

prokaryotic cells

What are the external layers of prokaryotes

glycocalyx, capsule, and slime layer

glycocalyx

surface covering composed of polysaccharide, polypeptide, or both

Capsule

well organized glycocalyx that is firmly attached to cell wall

Prokaryotic external structures

flagella, axial filaments, fimbriae, and pili

What helps prokaryotes attach

fimbrae

What helps prokaryotes transfer dna during conjugation

pili

Prokaryotic cell wall components

o-polysaccharides and lipopolysaccharides

Prokaryotic internal structures

cytoplasm, nucleoid region, ribosomes, potential endospores

Plasma membrane of eukaryotes

presence of cholesterol

Do eukaryotic cells have cytoplasm

yes

What structures are in eukaryotes

nucleus, rough endoplasmic reticulum, golgi apparatus, smooth endoplasmic reticulum and vesicles

Eukaryotic external structures

cell walls, glycocalyx, flagella and cilia

What do the cell walls of eukaryotes consist of

no peptidoglycan, material is dependent on oeganism

What is one item in Prokaryotes and Eukaryotes but have different structures

ribosomes, smaller in prokaryotes. cell wall, if present in eukaryotes then no peptidoglycan. flagella, one is made of flagellum one is microbtubules

What is something that is in eukaryotes and not prokaryotes

cholesterol, in membrane of eukaryotes. and organelles are only in eukaryotes

What is something that is in prokaryotes and not eukaryotes

endospores and peptidoglycan can only be present in prokaryotes

What is one word to describe the purpose of endospores

survival

What are the methods/types of microbial control

physical, chemical, and mechanical

Sterilization

removal of all microbial life

Disinfection

removal of vegetative pathogens

Antisepsis

removal of pathogens from living tissue

Sanitization

lower microbial count

Biocide/germicide

kills microbes

Microbiostatic

inhibiting growth

What are the physical methods of microbial control

heat, cold/desiccation, radiation, filters, and osmotic pressure

What are the types of heat microbial control

moist heat, dry heat, pasteurization

Moist heat

hot water, boiling water, steam/autoclave

Dry heat

oven or open flame

Pasteurization

a specific example of moist heat, reduces spoilage

How does cold help with microbial control

cold will lower the growth rate of many microbes but it is not a killing effect