Microbio Week 1- Test 1
100 Questions
23 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the smallest infectious particle between 18-600 nm?

  • Bacteria
  • Viruses (correct)
  • Fungi
  • Prions
  • What is an infectious protein with no DNA or RNA?

  • Bacteriophage
  • Virus
  • Prion (correct)
  • Viroid
  • What type of bacteria has no nuclear membrane and no membrane-bound organelles?

  • Eukaryotic bacteria
  • Prokaryotic bacteria (correct)
  • Protobacteria
  • Yeast (correct)
  • What type of fungi is unicellular?

    <p>Yeast</p> Signup and view all the answers

    What type of fungi is multicellular?

    <p>Mold</p> Signup and view all the answers

    What is the most complex group of microbes?

    <p>Parasite</p> Signup and view all the answers

    Which of the following is not an indication of an infection?

    <p>Syncope</p> Signup and view all the answers

    What is example of a pathogen/ infectious agent that causes single disease?

    <p>Tetanus toxin</p> Signup and view all the answers

    What is an example of a pathogen/ infectious agent that leads to several manifestations of a disease?

    <p>Staphylococcus Aureus</p> Signup and view all the answers

    What is an example of a pathogen/infectious agent in which the same disease can be caused by different microbes?

    <p>Meningitis</p> Signup and view all the answers

    What is an exogenous infection?

    <p>An infection caused by pathogens that originate from outside the body</p> Signup and view all the answers

    What is an endogenous infection?

    <p>An infection that originates from within the body</p> Signup and view all the answers

    Match each word to its definition

    <p>Microbiota = Normal flora Microbiome = microbial GENOMES in microbiota Prebiotic = foods that support growth of microbiota Probiotic = live organisms ingested for a believed benefit</p> Signup and view all the answers

    What percentage of the core microbiome is shared?

    <p>95%</p> Signup and view all the answers

    What is a characteristic of the secondary microbiome?

    <p>It is unique to the individual</p> Signup and view all the answers

    What is functional redundancy as it pertains to the microbiome?

    <p>The ability of different systems to perform the same function</p> Signup and view all the answers

    In which body system are opportunistic microbes not found?

    <p>Nervous System</p> Signup and view all the answers

    Which body system has the greatest microbiome diversity?

    <p>Digestive system</p> Signup and view all the answers

    What is decreased biodiversity in the genitourinary tract an indication of?

    <p>Good health</p> Signup and view all the answers

    What does an increase in microbiome diversity indicate in the genitourinary tract?

    <p>Increased risk of urinary tract infections</p> Signup and view all the answers

    What is not an example of microbes that can be found in the mouth?

    <p>Mold</p> Signup and view all the answers

    What is an example of a bacterial phyla that can cause common infections following a human bite wound?

    <p>Eikenella corrodens</p> Signup and view all the answers

    What pathogen can cause yeast infections in female vaginal tissue?

    <p>Candida albicans</p> Signup and view all the answers

    Match each opportunistic pathogen to its characteristics

    <p>P S E U D O M O N A S A E R U G I N O S A = Capsule, exotoxin A, environment (ubiquitous in nature and moist environment in hospital: flowers, sinks, toilets, ventilators, dialysis equipment) K L E B S I E L L I A S P = Virulence factor is the polysaccharide capsule S TA P H Y L O C O C C U S A U R E U S = -Contain catalase, coagulase, cytotoxins, exfoliative toxins, enterotoxins, toxic shock syndrome toxins • Antibiotic resistant: MRSA C O A G U L A S E N E G AT I V E S TA P H Y L O C O C C U S = Opportunistic infections with person to person spread and is found on human skin and mucosal surfaces</p> Signup and view all the answers

    Which of the following opportunistic pathogens has these characteristics: - Endogenous microbe colonizes gastrointestinal tract – spreads to other tissues if antibiotics are used; - Gram positive short chains similar to Streptococcus pneumoniae – able to survive on environmental surfaces for prolonged periods; - Cell wall with group D glycerol teichoic acid; - Can form biofilms and is antibiotic resistant (cephalosporins); - Most infections are endogenous, some patient to patient spread?

    <p>Enterococcus</p> Signup and view all the answers

    Which of the opportunistic pathogens below has the following characteristics? - Endogenous microbe in the nasopharynx or oropharynx, causes infection when spread to distal sites such as lungs, sinuses, ears, blood, and meninges; person-to-person spread is rare. - Ability to colonize the oropharynx and spread into normally sterile tissues; produces pneumolysin and IgA protease and has a capsule to evade phagocytosis. - Cell wall contains phosphorylcholine (C polysaccharide).

    <p>Streptococcus pneumoniae</p> Signup and view all the answers

    Which of the following opportunistic pathogens has the specified morphology: small gram-negative rods arranged in pairs?

    <p>Pseudomonas aeruginosa</p> Signup and view all the answers

    Which of the following opportunistic pathogens consists of gram-negative rods?

    <p>Klebsiella Sp.</p> Signup and view all the answers

    Which of the following opportunistic pathogens is comprised of gram positive cocci arranged in clusters?

    <p>Staphylococcus aureus</p> Signup and view all the answers

    Which of the following opportunistic pathogens is comprised of elongated gram-positive cocci in pairs (diplococcus) and short chains?

    <p>Streptococcus pneumoniae</p> Signup and view all the answers

    Which of the following opportunistic pathogens is comprised of gram-positive short chains similar to Streptococcus pneumoniae that are able to survive on environmental surfaces for prolonged periods of time?

    <p>Enterococcus</p> Signup and view all the answers

    Which of the following opportunistic pathogens grows on most media and has a grape-like odor and beta hemolysis?

    <p>Pseudomonas aeruginosa</p> Signup and view all the answers

    Which of the following opportunistic pathogens fits this description:

    • Causes community or hospital acquired pneumonia
    • Necrotic destruction of alveolar spaces
    • Formation of cavities in the lungs
    • Production of blood-tinged sputum
    • Also causes wound, soft tissue infections, and UTIs?

    <p>Klebsiella Sp.</p> Signup and view all the answers

    Which of the following opportunistic pathogens is associated with the following risk factors: Presence of foreign material such as a splinter or catheter, previous surgery, and use of antibiotics that suppress normal flora?

    <p>Staphylococcus aureus</p> Signup and view all the answers

    Which opportunistic pathogen poses an infectious risk to the following patients:

    • Scalded skin syndrome – infants
    • Impetigo or cutaneous infections – children with poor personal hygiene
    • Toxic shock syndrome – menstruating women
    • Bacteremia and endocarditis – intravascular catheters
    • Meningitis – patients with shunts
    • Pneumonia – patients with underlying compromised pulmonary function or respiratory virus infection?

    <p>Staphylococcus aureus</p> Signup and view all the answers

    What patients are NOT at risk of a coagulase negative staphylococcus infection?

    <p>Healthy individuals</p> Signup and view all the answers

    Which opportunistic pathogen poses risks to the following patient groups: young children with high levels of colonization, individuals with underlying respiratory conditions, children and the elderly at risk for meningitis, and those with hematologic disorders or asplenia at risk for fulminant sepsis?

    <p>Streptococcus pneumoniae</p> Signup and view all the answers

    Which infectious pathogen is a risk to the following patient population: - Patients hospitalized for prolonged periods - Patients on broad spectrum antibiotics (cephalosporins)?

    <p>Enterococcus</p> Signup and view all the answers

    Which opportunistic pathogen has the following characteristics:

    • Antibiotic-associated diarrhea
    • Toxin A: an enterotoxin that attracts neutrophils
    • Toxin B: a cytotoxin that increases permeability of the intestine wall and causes diarrhea
    • Colonizes the intestine of some healthy individuals (approximately 5%) and can lead to endogenous infection when on antibiotics?

    <p>Clostridium difficile</p> Signup and view all the answers

    Which of the following opportunistic pathogens fits the description: Gram negative facultative anaerobic bacillus?

    <p>Eikenella Corrodens</p> Signup and view all the answers

    Which of the following opportunistic pathogens fits this description: Yeast outside the body, yeast with pseudohyphae inside the body to true hyphae; Endogenous – colonizes skin, mucosal tissue; Exogenous – transmission in hospitals especially to immunocompromised, leading to invasive infection?

    <p>Candida albicans</p> Signup and view all the answers

    Which opportunistic pathogen are the following patients most at risk for?

    • cystic fibrosis
    • cancer
    • AIDS
    • indwelling medical devices
    • burn
    • eye injuries
    • non-healing diabetic wound

    <p>Pseudomonas aeruginosa</p> Signup and view all the answers

    Which opportunistic pathogen can cause the following diseases: toxin-mediated (food poisoning), toxic shock syndrome, scalded skin syndrome, pyogenic diseases such as impetigo, folliculitis, furuncles, carbuncles, and other systemic diseases?

    <p>Staphylococcus aureus</p> Signup and view all the answers

    Which of the following is not a way to diagnose Staphylococcus aureus?

    <p>X-ray imaging</p> Signup and view all the answers

    Which opportunistic pathogen can cause the following diseases: Subacute endocarditis, infections of foreign bodies such as catheter area, and UTI?

    <p>Coagulase Negative Staphylococcus</p> Signup and view all the answers

    Which opportunistic pathogen can cause the following diseases: Pneumonia, sinusitis and otitis media, meningitis, and bacteremia?

    <p>Streptococcus Pneumoniae</p> Signup and view all the answers

    Which opportunistic pathogen can cause the following diseases: UTI, peritonitis (polymicrobial), wound infections, bacteremia with or without endocarditis?

    <p>Enterococcus</p> Signup and view all the answers

    Which opportunistic pathogen can cause the following diseases:

    -Antibiotic associated diarrhea – 5 to 10 days following antibiotic initiation -Pseudomembranous colitis – severe with profuse diarrhea, abdominal cramping and fever – white plaques can form over colon tissue (pseudomembrane)?

    <p>Clostridium difficile</p> Signup and view all the answers

    Which of the following opportunistic pathogens is unaffected when treated with cephalexin and dicloxacillin and must be treated with penicillin, tetracycline, and chloramphenicol?

    <p>Eikenella Corrodens</p> Signup and view all the answers

    Which opportunistic pathogen can cause severe invasive disease in humans, specifically associated with pericarditis?

    <p>Eikenella corrodens</p> Signup and view all the answers

    Which opportunistic pathogen can cause the following diseases: Endocarditis, Pneumonia, CNS wounds, UTI?

    <p>Pseudomonas aeruginosa</p> Signup and view all the answers

    Which opportunistic pathogen has the following characteristics? • Produces a slime layer that enables adhesion to foreign bodies such as catheters and grafts. • The slime layer offers protection from phagocytosis.

    <p>Coagulase Negative Staphylococcus</p> Signup and view all the answers

    Which of the following opportunistic pathogens is both coagulase negative and mannitol salt negative?

    <p>Staphylococcus epidermidis</p> Signup and view all the answers

    Which opportunistic pathogen fits this description: catalase negative, susceptible to optochin, and soluble in bile?

    <p>Streptococcus pneumoniae</p> Signup and view all the answers

    Which opportunistic pathogen fits this description: Catalase negative, resistant to bile and optochin, L-pyrrolidonyl arylamidase positive?

    <p>Enterococcus</p> Signup and view all the answers

    Which of the following opportunistic pathogens is NOT gram-positive?

    <p>Klebsiella Sp.</p> Signup and view all the answers

    What can celiac disease lead to in the microbiome?

    <p>An imbalance of harmful bacteria (dysbiosis)</p> Signup and view all the answers

    Gram negative bacteria have LPS = endotoxin

    <p>True</p> Signup and view all the answers

    Match each word to its definition

    <p>Antiseptic = applied to living skin to reduction infection/sepsis Aseptic = free from infection Bactericidal = kills bacteria Bacteriostatic = stops bacteria from reproducing</p> Signup and view all the answers

    Match each word to its definition

    <p>Disinfectant = chemical liquid that kills bacteria Germicide = agent that destroys harmful microbes (antiseptic) Sanitization = reduce or eliminate pathogens on a surface Sterilization = making something free of bacteria or other microbe</p> Signup and view all the answers

    Which opportunistic pathogen can form endospores?

    <p>Clostridium difficile</p> Signup and view all the answers

    What is a fomite?

    <p>An inanimate object that can carry infectious agents</p> Signup and view all the answers

    Match each word to its definition

    <p>Physical sterilization = exposure to high heat and pressure Filtration sterilization = through appropriate filter Chemical sterilization = sterilants that effectively kill all microbes and viruses and depending on exposure time, also endospores Disinfection = inactivates most microbes on non-living surfaces</p> Signup and view all the answers

    Match each item to its sterilization protocol level

    <h1>Critical = surgical instruments, catheters and intravenous fluids (penetrate tissues) Semi-critical = gastrointestinal endoscopes, equipment for respiratory therapy (do not penetrate tissues) – high level of disinfectant Noncritical = bed linen, furniture, crutches, stethoscopes, blood pressure cuffs: items that may contact skin but do not penetrate intact skin</h1> Signup and view all the answers

    Match each word to its definition

    <p>Sanitization = Reduces microbial load of an object through application of heat or antimicrobial chemical Sterilization = Completely eliminates all vegetive cells, endospores, and viruses from an inanimate item Antisepsis = Reduces microbe load on skin or tissue through application of an antimicrobial chemical Degerming = Reduces microbial load on skin or tissue through gentle to firm scrubbing and use of mild chemicals</p> Signup and view all the answers

    What is an example of a natural disinfectant?

    <p>Vinegar</p> Signup and view all the answers

    Which bacterial species is used to ensure autoclaves work?

    <p>Bacillus stearothermophilus</p> Signup and view all the answers

    What is not a physical agent for disinfection?

    <p>Chlorine</p> Signup and view all the answers

    What has replaced Crede's method of instilling silver nitrate drops for neonate gonococcal conjunctivitis

    <p>Erythromycin ointment</p> Signup and view all the answers

    Which chemical agent is commonly used to prevent infections in burns?

    <p>Silver sulfadiazine</p> Signup and view all the answers

    Match each characteristic to its appropriate category

    <p>Eukaryote = Strands of DNA diploid; Contains sterols Prokaryote = Single, circular DNA, haploid;Absent of sterols except mycoplasma Eukaryote = 80S (60S + 40S) Prokaryote = 70S (50S + 30)</p> Signup and view all the answers

    Which medication blocks the D-alanine D-alanine structure?

    <p>Vancomycin</p> Signup and view all the answers

    Which medication interferes with the final dephosphorylation step, affects peptide transfer to the growing cell wall, and prevents the recycling of phosphobactprenol?

    <p>Bacitracin</p> Signup and view all the answers

    What protein is the target of penicillin and other beta-lactam antibiotics?

    <p>Peptidoglycan transpeptidase (Penicillin binding proteins -PBP)</p> Signup and view all the answers

    Which Toll-like receptor (TLR) is the target for teichoic acid?

    <p>TLR2</p> Signup and view all the answers

    Is peptidoglycan found in gram positive or gram negative?

    <p>It is found in both gram positive and gram negative</p> Signup and view all the answers

    Is teichoic acid found in gram positive or gram negative?

    <p>It is found in gram positive only</p> Signup and view all the answers

    Is LPS found in gram negative or gram positive

    <p>It is found in gram negative only</p> Signup and view all the answers

    Which Toll-Like Receptor (TLR) does Lipopolysaccharide (LPS) activate?

    <p>TLR4</p> Signup and view all the answers

    Are secretion systems in gram negative or gram positive

    <p>Gram negative</p> Signup and view all the answers

    Match each secretion system type to its description

    <p>Type 1 = Iron acquisition Type 2 = secretes hydrolases Type 3 (major virulence factor) = inject effector proteins into eukaryotic cells Type 4 = horizontal gene transfer in P. aeruginosa and H. influenzae</p> Signup and view all the answers

    Which secretion system type in gram-negative bacteria mediates cell-to-cell fusion and biofilm generation?

    <p>Type V</p> Signup and view all the answers

    Which secretion system type in gram-negative bacteria releases effector molecules targeting eukaryotic cells or other bacteria?

    <p>Type VI</p> Signup and view all the answers

    What color do acid-fast bacteria appear after being stained?

    <p>Red/ pink</p> Signup and view all the answers

    Which of these is not an example of an adherence virulence factor?

    <p>Toxins</p> Signup and view all the answers

    Which virulence factor is described as a loose polysaccharide or protein layer that is hard to phagocytose?

    <p>Capsule</p> Signup and view all the answers

    Which pathogen has a polypeptide capsule instead of a polysaccharide capsule?

    <p>Bacillus anthracis</p> Signup and view all the answers

    Which virulence factor is an acid that makes it hard to phagocytose?

    <p>Mycolic acid</p> Signup and view all the answers

    Which enzyme is a virulence factor that neutralizes hydrogen peroxide?

    <p>Catalase</p> Signup and view all the answers

    Which enzyme is a virulence factor that converts fibrinogen to fibrin?

    <p>Coagulase</p> Signup and view all the answers

    Which enzyme is a virulence factor important for cell membrane integrity?

    <p>Hydrolase</p> Signup and view all the answers

    Which enzyme is a virulence factor that lyses red blood cells (RBC)?

    <p>Hemolysin</p> Signup and view all the answers

    In which stage of the growth cycle are bacteria most susceptible to antibiotics?

    <p>Log phase (taking up nutrients; virulence down, metabolism up)</p> Signup and view all the answers

    What is quorum sensing?

    <p>A process of communication between bacterial cells based on population density.</p> Signup and view all the answers

    What is a bacteria that exhibits quorum sensing?

    <p>Listeria monocytogenes</p> Signup and view all the answers

    What is an example of an obligate aerobe bacteria?

    <p>Mycobacterium tuberculosis</p> Signup and view all the answers

    What is an example of an obligate anaerobe bacteria?

    <p>Clostridium perfringens</p> Signup and view all the answers

    What is a siderophore?

    <p>A molecule that binds and transports iron</p> Signup and view all the answers

    Which of the following organisms produce enterobactin as a siderophore?

    <p>Escherichia coli</p> Signup and view all the answers

    Endospore formers be gram negative

    <p>False</p> Signup and view all the answers

    Study Notes

    Infectious Particles and Agents

    • Smallest infectious particles range from 18-600 nm, known as viruses.
    • Prions are infectious proteins that lack DNA or RNA.
    • Prokaryotic bacteria lack a nuclear membrane and membrane-bound organelles.

    Types of Fungi

    • Yeasts are unicellular fungi.
    • Molds and mushrooms are examples of multicellular fungi.

    Microbial Complexity and Infections

    • Viruses are considered the most complex group of microbes.
    • Different pathogens can be responsible for a single disease, while some pathogens may cause multiple disease manifestations.
    • An example of a pathogen causing different manifestations is Streptococcus pneumoniae.

    Infection Definitions

    • An exogenous infection originates outside the body.
    • An endogenous infection develops from the body’s own microbiota.

    Microbiome Insights

    • Approximately 10-20% of the core microbiome is shared across individuals.
    • The secondary microbiome exhibits greater variability due to environmental influences.
    • Functional redundancy in the microbiome means that different species can compensate for each other's functions.

    Body Systems and Microbiota

    • The central nervous system generally does not harbor opportunistic microbes.
    • The gastrointestinal system displays the highest microbiomic diversity.
    • Decreased biodiversity in the genitourinary tract is often a sign of increased infection risk.

    Opportunistic Pathogens

    • Various opportunistic pathogens are distinguished by specific characteristics related to their infections.
    • Examples include:
      • Staphylococcus aureus linked to skin infections and pneumonia.
      • Clostridium difficile associated with antibiotic-associated diarrhea.

    Pathogen Risk Factors

    • Certain groups are particularly susceptible to infections from specific opportunistic pathogens, such as S. pneumoniae in children or S. aureus in individuals with skin conditions.
    • Risk factors for infections often include the presence of foreign materials, recent surgeries, or antibiotic use.

    Diagnostic Challenges

    • Not all diagnostic methods effectively identify each pathogen; for example, some pathogens are resistant to standard antibiotics.

    Virulence Factors and Mechanisms

    • Bacterial virulence factors include toxin production, capsule protection, and specific enzymes that aid in adherence or tissue invasion.
    • Quorum sensing allows bacteria to communicate and coordinate activities based on population density.

    Antibiotics and Bacterial Growth

    • Bacteria are most vulnerable to antibiotics during their logarithmic growth phase.
    • Endospore formation serves as a survival strategy for some bacterial species, allowing them to endure harsh conditions.

    Siderophores and Iron Acquisition

    • Siderophores are molecules that bind and transport iron in bacterial environments, aiding in nutrient acquisition.
    • Enterobactin is a specific siderophore produced by various enterobacteria.

    Other Key Definitions

    • A fomite is any inanimate object that can carry infectious agents.
    • Peptidoglycan is primarily found in gram-positive bacteria; gram-negative bacteria have an outer membrane containing lipopolysaccharide (LPS).
    • Antibiotic-associated diarrhea can occur after antibiotic treatment, highlighting disrupted gut flora balance.

    Clinical Relevance

    • Understanding the characteristics and behavior of various pathogens and their interactions with hosts is crucial for effective diagnosis, treatment, and prevention of infections.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Test your knowledge about the smallest infectious particles ranging from 18 to 600 nm. This quiz will cover various types and their characteristics. Challenge yourself to see how much you know about these microscopic agents.

    More Like This

    Γενικά για τους Ιούς
    9 questions
    Virus
    24 questions

    Virus

    UserFriendlySagacity4401 avatar
    UserFriendlySagacity4401
    Use Quizgecko on...
    Browser
    Browser