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test 5
chapters 11-15
351
Microbiology
Undergraduate 1
11/20/2013

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Term
What are the gram negative spirochetes
Definition

Treponema pallidum

Borrelia burgdorferi

Term
What are the gram negative spirillum? Are the urease positive or negative?
Definition
Helicobacter pylori (urease positive)
Campylobacter jejuni (urease negative)
Term
What is the gram negative vibrio? What are some characteristics of it?
Definition
Vibrio cholera
lactose negative
oxidase and glucose positive
Term
What are the gram negative aerobic cocci?
Definition
Neisseria gonorrhoeae
Neisseria meningitides
Moraxella catarrhalis
Term
What are the gran negative aerobic rods (coccobacilli)?
Definition
Bordetella pertussis
Legionella pneumophila
Haemophilus influenza
Brucella abortus
Term
What are the gram negative aerobic rods (bacilli)
Definition
Pseudomonas aeruginosa
Rhizobium leguminosarum
Term
What are the fast fermenting gram negative enterics
Definition
Klebsiella
Escherichia
Enterobacter
Term
What are the slow fermenting gram negative enterics
Definition
Serratia
Citrobacter
Term
What are the non-coliform enteric pathogens (gram negative enterics)
Definition
Proteus mirabilis
Yersinia entercolitica
Yersinia pestis
Term
What gram negative species cause gastrointestinal problems
Definition
Helicobacter pylori
Salmonella enteritidis
Salmonella typhi
Term
What gram negative species cause dental caries?
Definition
Streptococcus mutans, S. mitis, S. oralis, S. sanguis, S. gordonii, Lactobacillus acidophilus
Term
What gram negative species cause gingivitis
Definition
Streptococcus mutans, Fusobacterium and Actinobacteria (anaerobes)
Term
What microbes cause periodontal disease
Definition
Campylobacter jejuni, Treponema denticola, Porphyromonas gingivalis
Term
What microbes cause gastric and duodenal ulcers
Definition
Helicobacter pylori
Term
What microbes cause gastroenteritis
Definition
Salmonella, campylobacter, e. coli
Term
What microbe causes dysentery
Definition
shigella
Term
What microbe causes antibiotic associated diarrhea and pseudomembranous colitis
Definition
Clostridium difficile
Term
What microbe causes Asiatic cholera
Definition
vibrio cholerae
Term
What microbes cause food poisoning
Definition
+Staphylococcus aureus
+Bacillus cereus
+Clostridium perfringens
+Clostridium botulinum

Campylobacter jejuni
Salmonella typhimurium
Escherichia coli O157:H7
Term
What are some common bacterial foodborne pathogens
Definition
Gram Positives:
Bacillus cereus
Listeria monocytogenes
Staphylococcus aureus
Streptococcus
Vibrio parahaemolyticus
Vibrio vulnificus

Gram negatives:
Escherichia coli
Shigella spp.
Vibrio cholera
Yersinia enterocolitica
Term
What microbes cause food infections
Definition
Salmonella
E. Coli O157:7
Campylobacter jejuni

+Listeria monocytogenes: Listeriosis
Term
What microbes cause general respiratory problems
Definition
Hemophilus influenza
Klebsiella pneumonia
Legionella pneumophila
Pseudomonas aeruginosa
Term
What microbes cause sinusitis
Definition
Haemophilus influenza
Pseudomonas aeruginosa
Term
What microbe causes strep throat
Definition
+ Streptococcus pyogenes
Term
What microbe causes diphtheria
Definition
+ Corynebacterium diphtheriae
Term
What microbes cause pneumonia
Definition
Gram positives:
Streptococcus pneumonia
Staphylococcus aureus
Streptococcus agalactiae
Mycoplasma pneumonia (atypical)
Moraxella catarrhalis

Gram negatives:
E. Coli
Pseudomonas aeruginosa
Haemophilus influenza
Chlamydophila pneumonia (atypical)
Legionella pneumonphila (atypical)
Klebsiella pneumonia
Term
What microbe causes whooping cough
Definition
- Bordetella pertussis
Term
What microbe causes tuberculosis
Definition
+ Mycobacterium tuberculosis
Term
What microbe causes chlamydia
Definition
Chlamydia trachomatis
Term
What microbe causes gonorrhea
Definition
Neisseria gonorrhoeae
Term
What microbe causes syphilis
Definition
Treponema pallidum
Term
What microbes cause UTI's
Definition
Escherichia coli
Proteus mirabilis
Enterobacter cloacae
Serratia marcescens
Pseudomonas aeruginosa
Klebsiella pneumonia (2nd most common)

+Staphylococcus aureus
Term
What microbes causes meningitis
Definition
Neisseria meningitides
Haemophilus influenza
Streptococcus pneumonia
Escherichia coli
Listeria monocytogenes
Term
What microbe causes otitis externa
Definition
- Pseudomonas aeruginosa
Term
What microbe causes otitis media
Definition
+Streptococcus pneumonia
-Haemophilus influenzae
Term
What microbe causes acne, boils, pimples, impetigo
Definition
+ Staphylococcus aureus
Term
What microbe causes hot tub itch, folliculitis, cellulitis
Definition
- Pseudomonas aeruginosa
Term
What microbes cause necrotizing fasciitis
Definition
Gram positives:
Streptococcus pyogenes
Staphylococcus aureus
Vibrio vulnificus
Clostridium perfringenes
Bacteroides fragilis
Term
What microbe causes anthrax (zoonoses)
Definition
+ bacillus anthracis
Term
What microbe causes Brucellosis (zoonoses)
Definition
- Brucella abortus
Term
What microbe causes Leptospirosis (zoonoses)
Definition
Leptospira
Term
What microbe causes Lyme disease (arthropod borne)
Definition
- Borrelia burgdorferi
Term
What microbe causes Ehrlichiosis (arthropod borne)
Definition
+Ehrlichia
Term
What microbe causes Rickettsiosis (Typhus, Rocky mountain spotted fever) -- arthropod borne
Definition
- Rickettsias
Term
What microbe causes plague?
Definition
- Yersinia pestis
Term
What microbe causes toxic shock syndrome and scaled skin syndrome
Definition
+ staphylococcus aureus
Term
What microbe causes scarlet fever
Definition
+ streptococcus pyogenes
Term
What microbe causes Hemolytic Uremic Syndrome (HUS)?
Definition
- E. Coli O157:H7
Term
What microbe causes diptheria
Definition
+ cornebacterium diphtheriae
Term
What microbes cause nosocomial infections
Definition
Gram positives: MRSA, Clostridium difficile

Gram negatives: Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Legionella pneumophila
Term
what are two groups of unrelated bacteria that are obligate intracellular parasites of eukaryotic cells?
Definition
Rickettsias and chlamydiae
Term
What microbes can be described as energy parasites, and why?
Definition
Chlamydiae are unable to produce enough ATP to sustain metabolism outside of a host cell
Term
What nosocomial infections can Acinetobacter baumanni cause?
Definition
bacteremia, secondary meningitis, and ventilator-associated pneumonia in ICU
Term
What are the aerobic gram-negative nonenteric bacilli (do not ferment sugars)?
Definition
pseudomonas, pseudomonas aeruginosa, brucella abortis, brucella suis, francisella tularensis, bordetella pertussis, legionella
Term
Where can you find the pseudomonas
Definition
free-living, soil, seawater, freshwater, plants, animals
Term
Describe the characteristics of the pseudomonas
Definition
small, gram-negative, single polar flagellum, oxidative, metabolically versatile (protease, amylase, pectinase, cellulase)
Term
What is most at risk for infections by pseudomonas aeruginosa
Definition
burn patients and people with cystic fibrosis
Term
What infections does -pseudomonas aeruginosa cause?
Definition
pneumonia, UTI, abscess, ear and eye infections, septicemia, endocarditis, meningitis, bronchopneumonia, corneal infectiosn with contacts, skin rashes
Term
What type of pathogen is -pseudomonas aeruginosa and what is it resistant to?
Definition
opportunistic pathogen to the debilitated or immunocompromised. Resists soaps, dyes, quats, drugs, drying and heat. Chronic nosocomial pathogen.
Term
What zoonosis does -Brucella cause? How do they affect animals and humans?
Definition
Brucella abortis (cows)
Brucella suis (pigs)
Brucellosis = Malta fever, undulant fever, Bang's disease.

In animals, it crosses the placenta and causes abortion

In humans, causes fever, chills, sweating, headache, muscle pain, weakness, weight loss, focal infections in the liver, spleen, bone marrow and kidneys.
Term
What does -Francisella tularensis cause?
Definition
Tularensis- Rabbit fever- vectors include rabbits, rodents, wild animals, arthropods. Causes headache, backache, fever, chills, weakness, pharyngitis, conjunctivitis, swollen glands.
Term
What are the virulence factors of -Bordetella pertussis
Definition
Whooping cough
Receptors bind to ciliated epithelium. Toxins kill cells, build up mucus and block airways.
Term
What are the two stages of whooping cough
Definition
-Bordetella pertussis

1. catarrhal stage: cold-like
2. paroxysmal stage: coughing fits, "whooping"
Term
What does -Legionella cause
Definition
Legionnaire's disease: rising fever, cough, diarrhea, abdominal pain, lung consolidation, impaired respiration, impaired function
Term
Describe the characteristics of Legionella pneumophila
Definition
gram-negative motile short rods, filaments, fastidious. Found in fresh water, aerosols, nosocomial
Term
Describe the Enterobacteriacae
Definition
Gram-negative, small non-spore forming rods, aerobic, ferment when no O2, facultative anaerobes. Found in soil, water, decaying matter, large bowel. Ferment glucose, nitrates to nitrites, oxidase negative, catalase positive, often motile
Term
What is the difference between the coliforms and noncoliforms of the enterobacteriacae?
Definition
coliforms ferment lactose quickly and noncoliforms are non or slow lactose fermenters
Term
What are some virulence factors of the enterobacteriacae?
Definition
endotoxins overcome the host defenses quickly and multiply. Also enterotoxins, capsules, hemolysins, fimbrae to colonize the host.
Term
What are some antigens of the enterobacteriacae?
Definition
flagellar (H)
capsule/fimbri (K)
somatic=cell wall = LPS (O)
Term
What is the most common enterobacteriacae coliform? Describe some characteristics of it? diseases it causes?
Definition
Escherichia coli
enterotoxigenic
enteroinvasive
enteropathogenic (wasting disease of newborns)

-infantile diarrhea
-traveler's diarrhea
Term
what are some enterobacteriacae coliforms?
Definition
-Klebsiella pneumonia
-Enterobacter
-Hafnia
-Citrobacter
-Serratia
Term
What diseases can Klebsiella pneumonia cause?
Definition
nosocomial prneumonai, meningitis, bacteriemia, wound infections, UTI
Term
What diseases can -Proteus cause?
Definition
UTI, wounds, pneumonia, septiciemia, infant diarrhea, burns
Term
What are some non-coliform pathogens that cause zoonoses
Definition
Salmonella enteriditis
S. paratypi
S. schottmulleri
S. hiirschfield
S. typhimurium
Term
Describe -Salmonella typhi. What does it cause?
Definition
gram negative noncoliform pathogen. cause typhoid fever. motile. adheres to mucosa of small intestine, progressive invasion that leads to septicemia, then to the lympht nodes, then to the liver and spleen, and ultimately cause bacteremia.

causes fever, diarrhea, abdominal pain
Term
Describe -Shigella
Definition
noncoliform pathogen. gram negative. causes shigellosis (sever abdominal cramps, watery stool with mucus and blood). also shigella dysentery when it invates the villi of the large intestine.

non-motile, no capsule, not fastidious, no H2S or urease.
Term
what are some virulence factors of -Shigella
Definition
endotoxin- fever enterotoxin. causes inflammation, degeneration of the villi, bleeding, heavy mucus production.

Shiga toxin- heat-labile exotoxin

infective dose = 200 cells
Term
Describe -Yersinia pestis
Definition
Nonenteric. Causes plague. Gram negative rod. Bipolar stain.
Term
What are some virulence factors of Yersinia pestis
Definition
capsular and envelope proteins protect against phagocytosis and promote intracellular growth. also coagulase, endotoxin.
Term
What are the three types of plague?
Definition
1. bubonic- bite to lymph node, inflammation = bubo. fever, chills, nausea

2. septicemic: coagulate blood in vessels, subcutaneous hemmorage, purpura to necrosis to gangrene

3. pneumonic: lungs, fatal
Term
What are the oxidase-positive nonenteric pathogens?
Definition
-pasteurella multocida (zoonose)
-haemophilus
-h. influenza
-h. aegyptius
-h. ducreyi
Term
Describe -Haemophilus
Definition
tiny gram-negative pleomorphic rods. fastidious, sensitive. REquire blood for hemitin (x factor), cytochromes, catalase, peroxidase
Term
what does -h. influenza cause
Definition
acute bacterial meningitis
Term
what does -h. aegyptius cause?
Definition
conjunctivitis/pink eye. subconjunctival hemorrhage
Term
what does -h. ducreyi cause
Definition
chancroid -STD- painful necrotic ulcer on genitalia. lymph nodes swell like buboes.
Term
What viruses cause the common cold
Definition
rhinoviruses and coronaviruses- no cure
Term
What virus causes influenza (the flu)
Definition
influenza (H1N1)- vaccination - avian and swine flu. cause by RNA viruses transmitted through the air
Term
What virus causes Rabies (describe)
Definition
Rabies virus
causes acute encephalitis
spread through animal bites
travels to the brain by following the peripheral nerves
fatal once it reaches the CNS and symptoms begin to show
Term
What viruses cause the common cold
Definition
rhinoviruses and coronaviruses- no cure
Term
What virus causes influenza (the flu)
Definition
influenza (H1N1)- vaccination - avian and swine flu. cause by RNA viruses transmitted through the air
Term
What virus causes Rabies (describe)
Definition
Rabies virus
causes acute encephalitis
spread through animal bites
travels to the brain by following the peripheral nerves
fatal once it reaches the CNS and symptoms begin to show
Term
What virus causes chicken pox
Definition
varicella-zoster virus
Term
Describe yellow fever
Definition
virus that is transmitted through the bite of the Aedes species of mosquitos. causes jaundice, fever, damaged liver and sometimes kidney fever. has a vaccine that can prevent it for ten years.
Term
What viruses cause pneumonia
Definition
influenza virus A and B, Respiratory syncytial virus (RSV), and Human parainfluenza viruses (in children). can get into the lungs and respiratory system, causing fever and difficulty breathing.
Term
What virus causes polio (describe)
Definition
poliomyelitis. acute viral infectious disease spread from person to person via the oral-fecal route. 90% of polio infections cause no symptoms. Range of symptoms if it enters the bloodstream. Oral vaccines given for treatment.
Term
What virus causes Measles (Rubeola)-describe
Definition
paramyxovirus of the genus Morbillivirus. enveloped, single-stranded, negative-sense RNA virus. Symptoms include fever, cough, runny nose, red eyes and rash. Contracted through the air like the flu. White dots in the throat are common. Vaccines available.
Term
Describe rotavirus
Definition
the most common cause of severe diarrheal disease in infants and young children globally. accounts for more than half a million deaths a year due to dehydration. General double-stranded RNA virus. Vaccines available.
Term
Describe norovirus
Definition
RNA virus that causes 90% of epidemic non-bacterial outbreaks of gastroenteritis around the world. REsponsibel for 50% of all foodborne outbreaks of gastroenteritis in the US. Transmitted by faecally contaminated food or water, person to person contact, or aerosolization of the virus and contamination of surfaces.
Term
Describe herpes virus
Definition
sexually transmitted disease that affects one in five adults in the US. infects nerves and has cycles of infection. The structure of the herpes viruses consist of a relatively large double-stranded, linear DNA genome encased within an icosahedral protein cage called a capsid, which is wrapped in a lipid bilayer called the envelope.
Term
Describe hepatitis
Definition
type A and B have vaccines
types A through E are common
can be spread through improper food handling and needle sharing.

Viral hepatitis can be caused by Hep A-E, herpes simplex, cytomegalovirus, Epstein-barr, yellow fever, and adenoviruses.
Term
Describe yellow fever virus
Definition
spread by mosquitos. common problem in tropical areas. causes jaundice. there is a vaccine, but no treatment once someone is infected. fifty percent die once they are in teh toxic phase.
Term
describe viral encephalitis
Definition
encephalitis = swelling aroudn the brain. viral sources are transmitted by mosquito bites. vaccine available.
Term
describe west nile virus
Definition
transmitted by mosquitos. brain swelling and death are common.
Term
describe HIV/AIDS
Definition
highly transmissible virus. can sit quietly in the immune system within our cells for many years. can mutate form one person to another, making it hard to develop a vaccine. Transmitted through blood transfusions, unprotected sex, sharing needles. There are now HIV vaccinations that make AIDS more survivable.
Term
describe human papillomavirus
Definition
common STD that is hard to test for in men. More than 30-40 types are transmitted through sexual contact and infect the anogenital region. Closely associated with genital wards but is also linked to cervical cancer. There is a vaccine.
Term
Describe mumps (virus)
Definition
painful swelling of the salivary glands (parotid gland). disease is self-limiting, no specific treatment besides controlling the symptoms with painkillers.
Term
define prodrome (medicine)
Definition
an early symptom or set of symptoms that might indicate the start of a disease before specific symptoms occur.
Term
Describe rubella (virus)
Definition
german measles. infection fot eh mother during pregnancy can be serious. child may be born with congenital rubella syndrome, which is a range of serious incruable illnesses. Spontaneous abortion can occur in up to 20% of cases.
Term
Describe SARS virus
Definition
Severe acute respiratory syndrome. Caused by the SARS coronavirus.
Term
Describe the structure of viruses
Definition
contain a single type of nucleic acid (DNA or RNA) and a protein coat, sometimes enclosed by an envelope composed of lipids, proteins, and carbohydrates.
Term
Describe how viruses work
Definition
they are obligatory intracellular parasites. they multiply by using the host cell's synthesizing machinery to cause the synthesis of specialized elements that can transfer the viral nucleic acid to other cells.
Term
What does host range mean
Definition
the spectrum of host cells in which a virus can multiply. most viruses infect only specific types of cells in one host species
Term
What is host range determined by
Definition
the specific attachment site on teh host cell's surface and the availability of host cellular factors
Term
what is the viral size
Definition
20 to 1000 nm in length. ascertained by electron microscopy.
Term
Describe the nucleic acid of viruses
Definition
viruses contain either DNA or RNA, and the nucleic acid may be single or double stranded, linear or circular, or divided into several separate molecules.
Term
Describe viral capsids and envelopes
Definition
the protein coat surrounding the nucleic acid of a virus is called the capsid. the capsid is composed of subunits, capsomeres, which can be a single type of protein or several types. The capsid of some viruses is enclosed by an envelope consisting of lipids, proteins, and carbs. Some envelopes are covered with carb-protein complexes called spikes.
Term
Describe helical viruses
Definition
ex: ebola virus.
resemble long rods, capsids are hollow cylinders surrounding the nucleic acid
Term
Decribe polyhedral viruses
Definition
ex: adenovirus
many-sided. usually the capsid is an icosahedron
Term
Describe enveloped viruses
Definition
covered by an enveope and are roughly spherical but highly pleomorphic.

enveloped helical viruses: influenza
enveloped polyhedral viruses: Simplexvirus
Term
Describe complex viruses
Definition
have complex structures. many bacteriophages have a polyhedral capsid with a helical tail attached.
Term
How are viruses classified
Definition
based on what type of nucleic acid, their strategy for replication and their morphology
Term
How are virus families and genuses named
Definition
family names end in -viridae; genus names end in -virus
Term
What is a viral species
Definition
a group of viruses sharing the same geneticf information and ecological niche
Term
how are viruses grown
Definition
in living cells
Term
what are the easiest viruses to grow
Definition
bacteriophages
Term
what is the plague method
Definition
a method to grow viruses in the lab. mixes bacteriophages with host bacteria and nutrient agar.

after several viral multiplication cycles, the bacterial in the area surroudnign the original virus are destroyed; the area of lysis is called a plaque.

each plaque originates with a single viral particle; teh concentraion of viruses is given as plaque-forming units
Term
Describe some aspects of growing animal viruses in the lab
Definition
sometimes requires whole animals.
simian AIDS and feline AIDS provide models for studying human AIDS.
some animal viruses can be cultivated with embryonated eggs.
viral growth can cause cytopathic effects in cell culture.
Term
what are cell cultures
Definition
cells growing in culture media in the lab
Term
how can viruses be identified
Definition
serological tests
RFLPs
PCR
Term
describe viral multiplication
Definition
viruses do not contain enzymse for energy production or protein synthesis. For a virus to multiply, it must invade a host cell and direct the host's metabolic machinery to produce viral enzymes and components.
Term
describe the lytic cycle
Definition
a phage causes the lysis and death of a host cell.
Term
describe lysogeny
Definition
some viruses can have their DNA incorporated as a prophage into the DNA of the host cell.
Term
Describe the attachment phase of the lytic cycle
Definition
sites of the phage's tail fibers attach to complementary receptor sites on the bacerial cell.
Term
Describe the penetration phase of the lytic cycle
Definition
phage lysozyme opens a portion of the bacterial cell wall, the tail sheath contracts to force the tail core thorugh the cell wall, and phage DNA enters the bacterial cell. Capsid remains outside.
Term
Describe the biosynthesis phase of the lytic cycle
Definition
transcription of phage DNA produces mRNa coding for proteins necessary for phage multiplication. Phage DNA is replicated, and capsid proteins are produced.
Term
Describe the eclipse period of the lytic cycle
Definition
separate phage DNA and protein can be found.
Term
Describe maturation during the lytic cycle
Definition
phage DNA and capsids are assembled into complete viruses.
Term
Describe the release phase of the lytic cycle
Definition
phage lysozyme breaks down the bacterial cell wall, and the new phages are released.
Term
Describe the lysogenic cycle
Definition
prophage genes are regulated by a erpressor coded for by the prophage. The prophage is replicated each time the cell divides.
Term
What can cause a cell to switch from the lysogenic cycle to the lytic cycle
Definition
exposure to certain mutagens can lead to excision fothe prophage and initiation of the lytic cycle.
Term
What are the effects of lysogeny
Definition
lysogenic cells become immune to reinfection with the same phage and may undergo phage conversion
Term
How can a lysogenic phage transfer bacterial genes
Definition
A lysogenic phage can transfer bacterial genes form one cell to another through transduction. Any genes can be trasnferred in gernealized transduction, and specific genes can be trasnferred in specialized transduction.
Term
how do animal viruses attach to the host
Definition
they attach to the plasma membrane of the host cell
Term
how does entry of animal viruses occur
Definition
receptor-mediated endocytosis or fusion
Term
Where does multiplication of animal viruses occur
Definition
int eh cytoplasm of the host cell
Term
What does retroviridae reverse transcriptase do
Definition
transcribes DNA from RNA
Term
How are viruses relased in animal cells
Definition
budding= method of release adn envelope formation
nonenveloped viruses are released through ruptures in the host cell membrane
Term
what transforms normal cells to concerous cells
Definition
activated oncogenes
Term
What are oncogenic viruses
Definition
viruses capable of producing tumors
Term
what can a provirus do
Definition
remain latent, produce viruses, or transform the host cell
Term
what is a latent viral infection
Definition
one in which the virus remains in teh host cell for long periods without producing an infection (cold sores and shingles)
Term
what are persistent viral infections
Definition
disease processes that occur over a long period and are generally fatal. caused by conventional viruses; viruses accumulate over a long period
Term
what are prions
Definition
infectious proteins first discovered inteh 1980's.
Term
what do prion diseases involve? examples?
Definition
involve the degeneration of brain tissue.
CJD and mad cow disease
Term
what causes prion diseases
Definition
they are the result of an altered protein. teh cause can be a mutation in the normal gene for PrPC or contact with an altered protein .
Term
How to plant viruses enter the host
Definition
through wounds or with invasive parasites like insects
Term
what are viroids
Definition
infectious pieces of RNA that cause some plant diseases, sucha s potato spindle tuber disase and cocanut cadang cadang viroid
Term
describe contagious cancer
Definition
a parasitic cancer or transmissibe cancer is a cancer cell or cluster of cancer cells that can be transmitted form animal to animal.
ex: devil facial tumour disease.
Term
what are pathogens
Definition
disease-causing microbes
Term
what is pathology
Definition
the study of disease
Term
what etiology
Definition
the cause of disease
Term
what is pathogenesis
Definition
the development of disease
Term
what is infection
Definition
the invasion and growth of pathogens in the body
Term
what is disease
Definition
an abnormal state in which part or all of hte body is not properly adjusted or is incapable of performing its normal functions
Term
define normal microbiota
Definition
microbes that establish permanent colonies inside or on teh body without producing disease
Term
define transient microbiota
Definition
microbes that are present for various periods and then disappear
Term
what is microbial antagonism
Definition
when normal microbiota prevent pathogens from causing an infection
Term
what is symbiosis
Definition
living together (normal microbes and the host)
Term
what is commensalism
Definition
one organism benefits, the other is unaffected
Term
what is mutualism
Definition
both organisms benefit
Term
what is parasitism
Definition
one organism benefits at the expense of the other
Term
example of commensalism
Definition
staphylococcus epidermidis on the skin and corynebacteria that inhabit the surface of the eye
Term
example of mutualism
Definition
e.coli that synthesizes vitamins K and B in the gut
Term
example of parasitism
Definition
disease-causing bacteria
Term
what are opportunistic microbes
Definition
microbes that do not cause disease under normal conditions but cause disease under special conditions (e.coli)
Term
What are Koch's postulates
Definition
1. the same pathogen must be present in every case of the disease
2. the pathogen must be isolated in pure culture
3. the pathogen isolated from pure culture must cause the same disease in a healthy, susceptible lab animal
4. teh pathogen must be re-isolated from the inoculated lab animal
Term
what are some exceptions to Koch's postulates
Definition
1. things that cannot grow on artifical media
2. some disease have unequivocal signs and symptoms
3. some disease (pneumonia) may be caused by a variety of microbes
4. some pathogens (S. pyogenes) can cause different diseases.
5. some diseases (HIV) affect humans only.
Term
what are symptoms
Definition
subjective changes in body functions
Term
what are signs
Definition
objective changes (measurable)
Term
what is a syndrome
Definition
a specific group of symptosm or signs that always accompanies a specific disease
Term
how are communicable diseases transmitted
Definition
directly or indirectly from one host to another
Term
what is a contagious disease
Definition
one that is easily spread
Term
what is disease incidence
Definition
number of people contracting the disease
Term
what is disease prevalenec
Definition
number of cases at a particular time
Term
what is an acute disease
Definition
one that develops rapidly but lasts a short time (influenza)
Term
what is a chronic disease
Definition
develops slowly, but is likely to continue or recur for long periods (tuberculosis, hep B)
Term
what is a subacute disease
Definition
one that is intermediate between acute and chronic (sclerosing panencephalitis)
Term
what is a latent disease
Definition
oen in which the causative agent remains inactive for a time but then becomes active to produce symptoms (shingles)
Term
what is herd immunity
Definition
the presence of immunity to a disease in most of the population
Term
what is a local infection
Definition
affects a small area of the body
Term
what is a systemic infection
Definition
spread throughout the body via the circulatory system.
Term
what is a focal infection
Definition
a local infection that spread systemically to another spot on the body, where it is located.
Term
what is a primary infection
Definition
an acute infection that causes the initial illness
Term
what is a secondary infection
Definition
one that can occur after the host is weakened from a primary infection
Term
what is an inapparent or subclinical infection
Definition
one that does not cause any signs of disease in the host
Term
what is a predisposing factor
Definition
something that makes the body more susceptible to disease or alters the course of a disease (age, gender, climate, fatigure, poor nutrition)
Term
what is the incubation period
Definition
the interval between the initial infection and the first appearane of signs and symptoms.
Term
what is the prodromal period
Definition
characterized by the appearane of teh first mild signs and symptoms
Term
what is the period of illness
Definition
the diease is at its height,a nd all disease signs and symptoms are apparent.
Term
what is the period of decline
Definition
the signs and symptoms subside
Term
what is the period of convalescence
Definition
the body retursn to its prediseased state and health is restored.
Term
what are the five stages to the development of a disease
Definition
1. incubation period.
2. prodromal period.
3. period of illness
4. period of decline
5. period of convalescence.
Term
what is a reservoir of infection
Definition
a continual source of infection
Term
what are zoonoses
Definition
diseases that affect wild and domestic animals and can be transmitted to humans
Term
what is droplet transmission
Definition
transmission via saliva or mucus in coughing or sneezing.
Term
what is vehicle transmission
Definition
transmission by a meidum such as water, food, or air
Term
what is airborne transmission
Definition
pathogens carried on water droplets or dust for a distance greater than one meter
Term
how do arthropod vectors transmit disease
Definition
1. mechanical (flies carrying the diease on them, spores, etc.. ex: cholora)
2. biological (malaria)
Term
what is a nosocomial infection
Definition
any infection tha tis acquired during the course of stay in a hospital
Term
what is a health care associated infection
Definition
include infections that are acquired in a setting other than a hospital
Term
how many hospital patients acquire nosocomial infections
Definition
5-15%
Term
how are normal microbes responsible for nosocomial infections
Definition
when they are introduced into the body through such medical procedures as surgery and catheterization
Term
what bacteria are the most frequent causes of nosocomial infections
Definition
opportunistic, drug-resistant, gram-negative bacteria
Term
how are nosocomial infections transmitted
Definition
through direct contact between staff members and patients and between patients, and through fomites such as catheters, syringes, and respiratory devices.
Term
what are emerging infectious diseases
Definition
new diseases and diseases that are increasing in incidence
Term
what leads to emerging infectious diseases
Definition
the use of antibiotics and pesticides, climatic changes, travel, the lack of vaccinations, and improved case reporting
Term
who is responsible for surveillance and response to emerging infectious diseases
Definition
the CDC, NIH, and WHO
Term
what is the science of epidemiology
Definition
the study of the transmission, incidence, and frequency of disease
Term
what is descriptive epidemiology
Definition
data about infected people are collected and analyzed
Term
what is analytical epidemiology
Definition
a group of infected people is compared with an uninfected group
Term
what is experimental epidemiology
Definition
controlled experiments designed to test hypotheses are performed
Term
what does case reporting do
Definition
it provides data on incidence and prevalence to local, state, and national health officials
Term
what is pathogenicity
Definition
the ability of a pathogen to produce a disease by overcoming the defenses of the host
Term
what is virulence
Definition
the degree of pathogenicity
Term
what is the portal of entry
Definition
the specific route by which a particular pathogen gains access to the body
Term
what is the parenteral route (portal of entry)
Definition
when some microbes gain access to tissues by inoculation through the skin and mucous membranes in bites, injections, and other wounds. route of penetration
Term
what are some common portals of entry
Definition
mucous membranes of the conjunctiva and the respiratory, gastrointestinal, and genitourinary tracts. Most microbes cannot penetrate intact skin- they enter hair follicles and sweat ducts
Term
what is the preferred portal of entry
Definition
many microbes can cause infections only when they gain access through their specific portal of entry
Term
what is LD50?
Definition
lethal dose for 50% of the inoculated hosts - a way of expressing virulence
Term
what is ID50?
Definition
infectious dose for 50% of the inoculated hosts- a way of expressing virulence
Term
how do pathogens adhere to the host?
Definition
surface projections on a pathogen called adhesins (ligands) adhere to complementary receptors on the host cells.
Term
what are adhesins
Definition
surface projections on a pathogen. They can be glycoproteins or lipoproteins and are frequently associated with fimbriae.
Term
What is the most common receptor on host cells for pathogens?
Definition
mannose
Term
what effect do biofilms have on pathogenicity?
Definition
they provide attachment and resistance to antimicrobial agents
Term
what is the purpose of a capsule
Definition
they prevent the cell from being phagocytized
Term
what is the function of proteins in the cell wall of pathogens?
Definition
proteins in the cell wall can facilitate adherence or prevent a pathogen from being phagocytized
Term
what does coagulase do? why is this important?
Definition
local infections can be protected in a fibrin clot caused by the bacterial enzyme coagulase
Term
what are kinases?
Definition
enzymes that destroy blood clots and facilitate the spread of bacteria from a focal infection
Term
what are hyaluronidases?
Definition
bacterial enzymes that destroy a mucopolysaccharide that holds cells together and facilitates the spread of bacteria from a focal infection
Term
what are collagenases?
Definition
bacterial enzymes that hydrolyze connective tissue called collagen and that help bacteria spread from focal infections
Term
what are the three enzymes that allow bacteria to spread from a focal infection
Definition
kinases, hyaluronidase, and collagenase
Term
what is antigenic variation
Definition
when microbes vary their expression of antigens in order to avoid the host's antibodies
Term
how to bacteria penetrate the host cell cytoskeleton
Definition
bacteria may produce proteins that alter the actin of the host cell's cytoskeleton allowing bacteria into the cell
Term
how do bacteria get iron from the host
Definition
siderophores
Term
how do bacterial pathogens directly damage host cells
Definition
host cells can be destroyed when pathogens metabolize and multiply inside host cells
Term
what are toxins
Definition
poisonous substances produced by microorganisms
Term
what is toxemia
Definition
the presence of toxins in the blood
Term
what is toxigenicity
Definition
the ability to produce toxins
Term
what are exotoxins
Definition
toxins produced by bacteria that are released into the surrounding medium. They produce the disease symptoms, not the bacteria
Term
what are antitoxins
Definition
antibodies produced against exotoxins
Term
describe A-B toxins
Definition
they consist of an active component that inhibits a cellular process and a binding component that attaches to the two portions to the target cell.
Ex: diphtheria toxin
Term
what do membrane-disrupting toxins cause
Definition
cell lysis
Ex: hemolysins
Term
what do superantigens do?
Definition
they cause the release of cytokines, which cause fever, nausea, and other symptoms (toxic shock syndrome toxin)
Term
What are endotoxins?
Definition
lipopolysaccharides (LPS), the lipid A component of the cell wall of gram-negative bacteria
Term
what causes the release of endotoxins
Definition
bacterial cell death, antibiotics, and antibodies
Term
what does the release of endotoxins cause
Definition
fever (by inducing the release of interleukin-1) and shock (because of a TNF-induced decrease in blood pressure)
Term
what do endotoxins allow bacteria to do?
Definition
cross the blood-brain barrier
Term
what is the Limulus amobocyte lysate assay used for?
Definition
to detect endotoxins in drugs and on medical devices
Term
what do plasmids do?
Definition
carry genes for antibiotic resistance, toxins, capsules, and fimbriae
Term
what can lysogenic conversion create?
Definition
bacteria with virulence factors, such as toxins or capsules
Term
how do viruses avoid the host's immune response?
Definition
by growing inside cells
Term
what are cytopathic effects (CPE)?
Definition
visible signs of viral infections
Term
what are cytocidal effects
Definition
cell death caused by a virus
Term
what are noncytocidal effects
Definition
damage to the cell (but not death) caused by a virus
Term
what are some cytopathic effects of viruses
Definition
stopping mitosis, lysis, formation of inclusion bodies, cell fusion, antigenic changes, chromosomal changes, and transformation
Term
what are symptoms of fungal infections caused by
Definition
capsules, toxins, and allergic responses.
Term
what are symptoms of protozoan and helminthic diseases caused by
Definition
damage to host tissue or by the metabolic waste products of the parasite
Term
how to some protozoa avoid destruction by the host's antibodies
Definition
they change their surface antigens while growing in a host
Term
what are some pathogenic properties of algae?
Definition
some can produce neurotoxins that cause paralysis when ingested by humans
Term
what are three common portals of exit for pathogens
Definition
1. the respiratory tract via coughing or sneezing
2. the gastrointestinal tract via saliva or feces
3. the genitourinary tract via secretions from the vagina or penis
Term
what is a portal of exit for microbes in the blood
Definition
arthropods and syringes
Term
Describe the Aquificae bacteria
Definition
thought to be the oldest branch of bacteria. Hyperthermophilic and Chemolithoautotrophic. They generate energy by oxidizing electron donors such as hydrogen, thiosulfate, and sulfur with oxygen as the electron acceptor
Term
Describe the Thermotogae bacteria
Definition
the second oldest branch of bacteria. Hyperthermophiles (80-90C). Gram negative rods with an outer sheath-like envelope that can balloon out from the ends of the cell. They grow in geothermal areas like marine hydrothermal vents. They are chemoheterotrophs with a functional glycolytic pathway. They can grow anaerobically on carbs and protein digests.
Term
Describe the Deinococcus-Thermus bacteria
Definition
Three genera- genus Deinococcus is the best studied.
Spherical or rod-shaped, often associated in pairs or tetrads.
They are aerobic, mesophilic, and catalase positive.
They stain gram positive but have a layered cell wall and an outer cell membrane like gram negative bacteria.
They are extremely resistant to desiccation and radiation.
Term
Describe the biology of deinococci
Definition
they can be isolated from ground meat, feces, air, fresh water, and other sources.
they have a genome that consists of two circular chromosomes (a mega plasmid and a small plasmid)
They have an unusual ability to repair chromosomal damage
Term
What are the three groups of photosynthetic bacteria
Definition
purple bacteria, green bacteria, and cyanobacteria
Term
describe cyanobacteria
Definition
they carry out oxygenic photosynthesis. they use water as an electron source for the generation of NADH and NADPH. They have chlorophyll a, which absorbs longer wavelengths of light. They are found mostly at the surface of bodies of water.
Term
describe purple sulfur bacteria
Definition
they use reduced sulfur compounds as electron sources and accumulate sulfur granules within their cells. They are anaerobes and use bacteriochlorophyll pigments.
Term
describe green sulfur bacteria
Definition
obligately anaerobic photolithoautotrophs. deposit sulfur granules outside of the cell. they lack flagella and are nonmotile. they are morphologically diverse.
Term
describe purple nonsulfur bacteria
Definition
they use organic molecules as their electron source. Anaerobic
Term
Describe green nonsulfur bacteria
Definition
filamentous, gliding bacteria. thermophilic. anoxygenic photosynthesis with organic compounds as carbon sources or can grou aerobically as a chemoheterotroph.
Term
where are the photosynthetic pigments of cyanobacteria located
Definition
in the thylakoid membranes
Term
how do cyanobacteria fix carbon dioxide
Definition
the calvin cycle
Term
what pathway plays an important role in the metabolism of cyanobacteria
Definition
the pentose phosphate pathway
Term
what are trichomes (cyanobacteria)
Definition
rows of bacterial cells that are in close contact with one another over a large area
Term
how do cyanobacteria reproduce
Definition
through binary fission, budding, fragmentation, and multiple fission
Term
what does fragmentation create
Definition
small motile filaments called hormogonia
Term
what are akinetes
Definition
thick-walled resting cells that are resistant to desiccation; they often germinate to form new filaments. formed by cyanobacteria
Term
Describe the phylum Chlamydia
Definition
nonmotile, coccoid, gram-negative bacteria.
Term
how do chlamydia reproduce
Definition
within the cytoplasmic vesicles of host cells by a unique developmental cycle involving elementary bodies and reticulate bodies
Term
describe the genomes of chlamydias
Definition
they have one of the smallest prokaryotic genomes
Term
what are the three human pathogens in the Phylum Chlamydiae
Definition
C. trachomatis, C. psittaci, and C. pneumoniae
Term
What does Chlamydia trachomatis cause
Definition
trachoma, nongonococcal urethritis, and other diseases in humans and mice
Term
What does Chlamydia psittaci cause
Definition
psittacosis in humans and infects many other mammals as well. invades the respiratory and genital tracts, the placenta, developing fetuses, they eye, and synovial fluid of the joints
Term
What does Chlamydia pneumonia cause
Definition
human pneumonia and possibly atherosclerosis and heart disease
Term
Describe the Phylum Spirochaetes
Definition
they are gram-negative, chemoheterotrophic, flexibly helical bacteria that exhibit a crawling motility due to a structure called an axial filament.
Term
What are some important members of the Phylum Spirochaetes
Definition
Treponema and Borrelia.
T. Ppallidum causes syphilis
B. burgdorferi causes Lyme disease
Term
Describe the proteobacteria
Definition
they are the largest and most diverse group of bacteria. Some believe that they arouse from a photosynthetic ancestor.
Term
What are the five classes of the proteobacteria
Definition
1. Alphaproteobacteria
2. Betaproteobacteria
3. Gammaproteobacteria
4. Deltaproteobacteria
5. Epsilonproteobacteria
Term
Describe the genera Rickettsia of the proteobacteria
Definition
they are in the alphaproteobacteria. They are either parasitic or mutualistic. They enter the host by phagocytosis, escape the phagosome, and then reproduce in the cytoplasm by binary fission. The host cell eventually bursts and releases the new organisms.
Term
What does Rickettsia ricketsii cause
Definition
rocky mountain spotted fever
Term
Describe Rhizobium leguminosarum
Definition
they are proteobacteria that grow symbiotically within the root nodules cells of legumes as nitrogen-fixing bacteroids
Term
Describe the genus Agrobacterium of the family Rhizobiaceae
Definition
they are not capable of nitrogen fixation. Invades crown, roots, and stems of many plants and transforms infected plant cells into autonomously proliferating tumors.
Term
What does Agrobacterium tumefaciens cause
Definition
causes crown gall disease by means of a tumor inducing plasmid
Term
Describe the genus Neisseria of the class Betaproteobacteria
Definition
they are nonmotile, aerobic, gram-negative cocci. They are inhabitants of the mucous membranes of animals and human pathogens.
Term
What cause gonorrhea
Definition
Neisseria gonorrhoeae
Term
what causes bacterial meningitis
Definition
Neisseria meningitidis
Term
Describe the genus Bordetella
Definition
gram-negative aerobic coccobacilli. Chemoorganotrophs with respiratory metabolism. They require organic sulfur and nitrogen in the form of amino acids for growth. They are mammaliam parasites that multiply in the respiratory epithelial cells.
Betaproteobacteria
Term
Describe Bordetella pertussis
Definition
nonmotile, encapsulated species that causes whooping cough
Term
What is the largest class of the proteobacteria
Definition
gammaproteobacteria
Term
Describe the genus Pseudomonas (gammaproteobacteria)
Definition
aerobic respiratory chemoheterotrophs. some are major animal and plant pathogens (P. aeruginosa)
Term
Describe the family Vibrionaceae (gammaproteobacteria)
Definition
gram-negative, straight or curved rods with polar flagella. They are oxidase-positive and use D-glucose as their sole or primary carbon and energy source. They are aquatic.
Term
Describe V. cholerae
Definition
causes cholera.
Term
Describe the order enterobacteriales
Definition
consists of one family containing over 41 genera. they are all gram-negative, peitrichously flagellated or nonmotile, facultatively anaerobic, straight rods with simple nutritional requirements.
Term
give some examples of enterobacteriales
Definition
Escherichia, proteus, salmonella, shigella, enterobacter, serratia, erwinia, klebsiella
Term
describe the class epsilonproteobacteria
Definition
the smallest of the proteobacteria groups. contains one order with two families. Campylobacter and Helicobacter are the most important genera. They are microaerophiles, motile, helical or vibroid, gram negative rods.
Term
describe the genus Campylobacter
Definition
epsilonproteobacteria.
C. jejuni- causes abortion in sheep and enteritis diarrhea in humans
Term
describe the genus helicobacter
Definition
epsilonproteobacteria
H. pylori- cause of gastritis and peptic ulcer disease. produces large quantities of urease and urea hydrolysis appears to be associated with their virulence.
Term
What is a lichen
Definition
a combination of a green alga (or a cyanobacterium) and a fungus.
Term
Describe protozoa
Definition
they are unicellular, eukaryotic organisms
Term
what is a trophozoite
Definition
the feeding and growing stage of a protozoan
Term
what is schizogony
Definition
multiple fission: the nucleus undergoes multiple divisions before the cell divides
Term
how do protozoans reproduce sexually
Definition
through conjugation
Term
what is protozoan encystment
Definition
under certain adverse conditions, some protozoa produce a protective capsule called a cyst. it permits the organism to survive when food, moisture, or oxygen are lacking, when the temperature is not suitable, or when there are toxic chemicals present.
Term
describe the nutritional requirements of protozoans
Definition
they are aerobic heterotrophs, although many are capable of anaerobic growth.
Term
what is a cytosome?
Definition
a mouth-like opening found on ciliated protozoans
Term
where does digestion take place on protozoans
Definition
in membrane enclosed vacuoles
Term
what is the name of a parasite that does not have mitochondria and creates cysts
Definition
Giardia lamblia (protozoan). causes giardiasis. diagnosed by cysts in the feces.
Term
what is the name for a protozoan that has an undulating membrane and lacks mitochondria
Definition
Trichomonas vaginalis.
Term
Describe euglenoids
Definition
protozoans. photoautotrophs. they have a semirigid plasma membrane called a pellicle. move by means of a flagella at the anterior end. they have an eyespot to sense light. they are facultative chemoheterotrophs.
Term
describe hemoflagellates
Definition
protozoans that are blood parasites. they are transmitted by the bites of blood feeding insects and are found in the circulatory system of the infected host. Includes the genus Trypanosoma.
Term
describe Amebae
Definition
protozoans that move by extending blunt, lobelike projections of the cytoplasms called pseudopods.
Term
what is the only pathogenic ameba
Definition
Entamoeba histolytica- found in the human intestine.
Term
describe the Apicomplexa
Definition
protozoans that are not motile in their mature forms and are obligate intracellular parasites. (Plasmodium)
Term
what is a sporozoite
Definition
the infective stage of plasmodium
Term
what is a merozoite
Definition
progeny of sporozoites that can infect RBCs
Term
what is a definitive host
Definition
the host that harbors the sexually reproducing stage of the bug (mosquito for malaria)
Term
what is the intermediate host
Definition
the host in which the parasite undergoes asexual reproduction (the human for malaria)
Term
describe ciliates
Definition
protozoans that have cilia that are similar to but shorter than flagella.
Term
what is the only ciliate that is a human parasite
Definition
Balantidium coli- causes a rare type of dysentary
Term
describe slime molds
Definition
protozoans that are closely related to amebae. Two types: cellular and plasmodial.
Term
Describe helminths
Definition
multicellular eukaryotic animals that generally possess digestive, circulatory, nervous, excretory, and reproductive systems.
Term
What differences can be made between parasitic helmintsh and their free-living relatives
Definition
parasitic helminthes may lack a digestive system, their nervous system is reduced, their means of locomotion is reduced, and their reproductive system is often complex
Term
describe the platyhelminths
Definition
flatworms. classes of parasitic flatworms include trematodes and cestodes.
Term
describe trematodes
Definition
flatworms that are called flukes. they obtain food by absorbing it through their nonliving outer covering, called the cuticle.
Term
describe cestodes
Definition
called tapeworms. they are intestinal parasites. their head is called the scolex. their body is made of segments called proglottids.
Term
describe nematodes
Definition
protozoans. roundworms. males are smaller than females. most species are dioecious.
Term
how do protozoans reproduce asexually
Definition
fission, budding, or schizogony
Term
how do cellular slime molds get their nutrition
Definition
they ingest bacteria by phagocytosis
Term
how do plasmodial slime molds get their nutrition
Definition
they engulf organic debris and bacteria as it moves
Term
what are the nematodes that infect humans with their larvae
Definition
hookworms and Trichinella
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