3.2.5 Microbiology

• What is the study of microscopic organisms called?

  Microbiology
• What are the three main types of microorganisms?

  Bacteria, fungi, viruses
• What type of organisms are fungi?

  Eukaryotic, multicellular
• Match the microorganism with its key feature:

  Bacteria ↔️ Lack a true nucleus

  Fungi ↔️ Have membrane-bound organelles

  Viruses ↔️ Require a host cell
• What is the purpose of disinfection in aseptic techniques?

  Reduce microorganisms to a safe level
• Steps in inoculation and culturing microorganisms:

  1️⃣ Inoculation

  2️⃣ Incubation

  3️⃣ Observation
• Incubation involves placing the inoculated medium in an incubator at a controlled temperature and humidity.

  True
• Match the step in culturing microorganisms with its purpose:

  Inoculation ↔️ Start microbial growth

  Incubation ↔️ Facilitate optimal growth

  Observation ↔️ Identify and analyze microorganisms
• What are the four main types of microorganisms studied in microbiology?

  Bacteria, viruses, fungi, protozoa
• Fungi are eukaryotic, multicellular organisms that include yeasts, molds, and mushrooms
• Aseptic techniques are used to prevent contamination by pathogenic microorganisms.


  True
• Sterilization involves the complete elimination of all microorganisms, including spores
• What is a growth medium used in microbiology?

  Nutrient broth or agar plate
• Match the type of microscopy with its description:

  Light microscopy ↔️ Uses visible light and lenses

  Electron microscopy ↔️ Uses beams of electrons
• PCR is a molecular technique used to amplify specific DNA sequences
• Serial dilution and plate counting only count viable cells.


  True
• What is the original CFU/mL if 0.1 mL of a 10^-5 dilution yields 135 colonies?

  1.35 \times 10^8</latex>
• What are the key factors affecting microbial growth?

  Temperature, pH, oxygen, nutrients
• Most bacteria thrive in neutral pH conditions (around pH 7)


  True
• Essential nutrients for microbial growth include carbon, nitrogen, phosphorus, and vitamins
• Understanding microbiology is essential for managing infectious diseases
• Bacteria are prokaryotic and lack a true nucleus.


  True
• Fungi are eukaryotic and include yeasts, molds, and mushrooms
• Arrange the following aseptic techniques in order from most to least rigorous:

  1️⃣ Sterilization

  2️⃣ Disinfection

  3️⃣ Antisepsis

  4️⃣ Sanitation
• Disinfection reduces the number of microorganisms to a safe level.


  True
• Match the aseptic technique with its example:

  Sterilization ↔️ Sterilizing surgical instruments

  Disinfection ↔️ Cleaning lab benches

  Antisepsis ↔️ Washing hands with antibacterial soap

  Sanitation ↔️ Sanitizing restaurant tables
• What are common techniques used for inoculation?

  Streaking or spreading
• What is the purpose of streaking in inoculation?

  Ensure even distribution
• Observation involves examining the culture for colonies and growth characteristics.


  True
• The purpose of incubation is to facilitate optimal microbial growth
• Match the steps of microbial culturing with their descriptions:

  Inoculation ↔️ Introducing microorganisms into a growth medium

  Incubation ↔️ Placing inoculated medium in an incubator

  Observation ↔️ Examining culture for colonies
• Gram staining differentiates bacteria based on their cell wall composition.


  True
• What does the catalase test detect?

  Catalase enzyme
• Molecular techniques aid in medical diagnostics, environmental monitoring, and industrial biotechnology
• Match the microbial observation methods with their descriptions:

  Microscopy ↔️ Allows visualization of microorganisms

  Staining techniques ↔️ Enhances visibility of microorganisms

  Culturing techniques ↔️ Grows microorganisms in specific media

  Biochemical tests ↔️ Identifies microbes based on metabolic capabilities

  Molecular techniques ↔️ Analyzes microbial DNA
• The direct count method counts both live and dead cells.


  True
• Which method provides a rapid estimation of microbial populations?

  Direct count
• Serial dilution and plate counting only counts viable cells.

  True
• What volume of the 10^-5 dilution was plated in the example problem?

  0.1 mL
• What is the original CFU/mL in the example problem?

  1.35 × 10^8 CFU/mL