Bacterial Structure and Organization Quiz
51 Questions
0 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 general organization of a bacterial cell?

  • Cell membrane and cytoplasm (correct)
  • Cell membrane, cytoplasm, and flagella
  • Cell wall, cytoplasm, and pili
  • Cell membrane, cell wall, and capsule

    • Which bacterial structure is responsible for protecting the cell from lysis due to changes in osmotic pressure?

  • Flagella
  • Periplasm
  • Pili/fimbriae
  • Capsule (correct)

    • What is the main function of the bacterial cell wall?

  • Provide structural support and shape to the cell (correct)
  • Facilitate cellular locomotion
  • Regulate the entry of nutrients into the cell
  • Facilitate genetic exchange between cells

    • Which component of the bacterial cell envelope is associated with adherence to host cells and tissues?

    <p>Pili/fimbriae</p> Signup and view all the answers

    What is the function of the plasma membrane in bacteria?

    <p>Barrier against aqueous ions</p> Signup and view all the answers

    What is the main function of peptidoglycan?

    <p>Structural support and shape</p> Signup and view all the answers

    Where is cardiolipin found in bacteria?

    <p>In the plasma membrane</p> Signup and view all the answers

    Which components of the bacterial cell wall differ between different types and species of bacteria?

    <p>Peptidoglycan layer</p> Signup and view all the answers

    What is the main function of the outer membrane in Gram-negative bacteria and Chlamydiaceae?

    <p>Selective barrier and protection against lysis</p> Signup and view all the answers

    What is present in the outer leaflet of the outer membrane?

    <p>Lipopolysaccharide (LPS)</p> Signup and view all the answers

    How does the outer membrane contribute to host mimicry and antigenic variation?

    <p>Via sugars (O-antigen) and proteins</p> Signup and view all the answers

    What is the function of the periplasm in bacteria?

    <p>Protection against osmotic lysis via solutes</p> Signup and view all the answers

    What is the major function of capsules in bacteria?

    <p>Antiphagocytic activity</p> Signup and view all the answers

    Which component is responsible for adhesion to surfaces and biofilm formation in bacteria?

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

    What is the main function of pili/fimbriae in bacteria?

    <p>Adhesion to host cell receptors</p> Signup and view all the answers

    What is the role of the 'K' antigen in some serotyping schemes of bacteria?

    <p>Vaccine target</p> Signup and view all the answers

    Which drug prevents the recycling of bactoprenol-PP during peptidoglycan synthesis?

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

    What is inhibited by Fosfomycin during peptidoglycan synthesis?

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

    Which drug inhibits alanine racemase and D-ala-D-ala synthetase during peptidoglycan synthesis?

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

    What does Tunicamycin prevent during peptidoglycan synthesis?

    <p>NAM-P to Und-P transfer</p> Signup and view all the answers

    Which antibacterial enzyme cleaves the bond between NAG and NAM in peptidoglycan?

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

    What is the primary function of the plasma membrane in bacteria?

    <p>Control over osmotic balance</p> Signup and view all the answers

    Which component forms a 3D multilayered net in the peptidoglycan structure?

    <p>Peptide tail</p> Signup and view all the answers

    What is the role of cardiolipin in the plasma membrane of bacteria?

    <p>Barrier against aqueous ions</p> Signup and view all the answers

    Where is the outer membrane absent in some genera or species of bacteria?

    <p>Gram-positive bacteria</p> Signup and view all the answers

    What type of bacteria has a variable outer membrane structure used for differentiating strains or species?

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

    What is added in phase II of PG biosynthesis in the presence of a bridge peptide?

    <p>Pentaglycine bridge</p> Signup and view all the answers

    Where does monomer production for PG biosynthesis occur?

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

    What is used for the production of many extracellular polysaccharides in phase I of PG biosynthesis?

    <p>Bactoprenol-PP</p> Signup and view all the answers

    What is responsible for incorporating the new monomer into the PG macromolecule in phase III of PG biosynthesis?

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

    Which type of drug inhibits transpeptidases and leads to cell lysis as autolysins continue to function by weakening the new peptidoglycan?

    <p>$\beta$-lactams (penicillins, cephalosporins, etc.)</p> Signup and view all the answers

    Which of the following bacterial genera is Gram-negative?

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

    What is a characteristic feature of the outer membrane of Gram-negative bacteria?

    <p>Containment of crystal violet during Gram staining</p> Signup and view all the answers

    Which type of bacteria has a cell wall structure that includes mycolic acids?

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

    Which staining technique is specifically used for acid-fast bacteria?

    <p>Ziehl-Neelsen stain</p> Signup and view all the answers

    Which bacterial genus is known for its resistance to chemicals and antibiotics due to its unique cell wall components?

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

    What is the main function of Penicillin-binding proteins (PBPs) in the peptidoglycan (PG) biosynthetic process?

    <p>Cleaving PG crosslinks to allow cell growth and separation</p> Signup and view all the answers

    Which bacteria have an outer membrane with lipopolysaccharides (LPS) but no peptidoglycan (PG)?

    <p>Chlamydia and Chlamydophila</p> Signup and view all the answers

    What is the main role of the protein layer in the context of bacterial cell wall biosynthesis?

    <p>Providing structural support to the bacterial cell wall</p> Signup and view all the answers

    Why is the Gram stain not useful for visualizing spirochetes such as Treponema and Borrelia?

    <p>They have a very thin structure that is not visible by light microscopy</p> Signup and view all the answers

    Which enzyme is responsible for removing the last D-alanine from peptide tails that have not been crosslinked in peptidoglycan (PG)?

    <p>DD-carboxypeptidase</p> Signup and view all the answers

    What is the main function of peptidoglycan in bacteria?

    <p>Protection against osmotic lysis</p> Signup and view all the answers

    Which statement best describes the biological effects of peptidoglycan?

    <p>Unique to bacteria and induces cytokines</p> Signup and view all the answers

    What role do teichoic and lipoteichoic acids play in Gram-positive bacteria?

    <p>Regulation of autolysis</p> Signup and view all the answers

    Which bacterial component is involved in adherence to host cells and tissues?

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

    What is the general role of adhesins in bacteria?

    <p>Facilitating adherence to host cells and tissues</p> Signup and view all the answers

    Which component is a specific type of peptidoglycan fragment targeting ciliated respiratory epithelial cells?

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

    What is the primary effect of teichoic and lipoteichoic acids in Gram-positive bacteria?

    <p>Regulation of autolysis</p> Signup and view all the answers

    What is the function of PAMPs (Pathogen Associated Molecular Patterns) in bacteria?

    <p>Inducing cytokines like IL-1, IL-6, GCSF, TNF</p> Signup and view all the answers

    What distinguishes teichoic and lipoteichoic acids from peptidoglycan in their role within Gram-positive bacteria?

    <p>Regulation of autolysis</p> Signup and view all the answers

    What is the key function of adhesins in bacteria?

    <p>Facilitating adherence to host cells and tissues</p> Signup and view all the answers

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser