WGU D311: Microbiology with Lab: Section 1
Describe the lytic cycle in bacteriophages.
✔️✔️ In the lytic cycle, a bacteriophage attaches to a bacterial cell, injects its DNA, uses the host’s
machinery to replicate and assemble new viruses, then lyses the cell to release them.
What is the significance of Koch's postulates?
✔️✔️ Koch's postulates are a set of criteria to establish a causative relationship between a microbe
and a disease, helping to identify pathogens responsible for specific illnesses.
How does the process of translation contribute to protein synthesis?
✔️✔️ During translation, ribosomes read the mRNA sequence and link amino acids in the correct
order to form a protein, based on the genetic code in the mRNA.
What is the purpose of an anaerobic chamber in microbiology?
✔️✔️ An anaerobic chamber creates an oxygen-free environment, allowing for the growth and study
of anaerobic organisms that cannot survive in the presence of oxygen.
Explain the role of pili in bacterial conjugation.
✔️✔️ Pili are hair-like structures on bacteria that facilitate conjugation by connecting two cells,
allowing the transfer of genetic material, such as plasmids, from one cell to another.
What is the function of catalase in cells?
✔️✔️ Catalase breaks down hydrogen peroxide, a toxic byproduct of cellular metabolism, into water
and oxygen, protecting cells from oxidative damage.
How do vaccines contribute to herd immunity?
✔️✔️ Vaccines reduce the spread of infectious diseases within a population, creating herd immunity
that protects individuals who cannot be vaccinated, such as those with immune deficiencies.
, Describe how binary fission enables bacterial reproduction.
✔️✔️ Binary fission is a process in which a bacterial cell replicates its DNA, elongates, and splits into
two identical daughter cells, allowing for rapid population growth.
What are obligate anaerobes, and where do they typically thrive?
✔️✔️ Obligate anaerobes cannot survive in oxygen and typically thrive in environments like deep soil,
sediments, or the human gastrointestinal tract, where oxygen is absent.
How does the structure of a Gram-positive cell wall differ from a Gram-negative cell wall?
✔️✔️ A Gram-positive cell wall has a thick peptidoglycan layer without an outer membrane, while a
Gram-negative cell wall has a thinner peptidoglycan layer and an outer lipid membrane.
Explain the function of ribosomal RNA (rRNA) in protein synthesis.
✔️✔️ Ribosomal RNA (rRNA) is a structural component of ribosomes that helps facilitate the assembly
of amino acids into proteins, providing a scaffold for translation.
What is the role of spores in fungal reproduction?
✔️✔️ Fungal spores serve as reproductive units, capable of growing into new fungi under favorable
conditions, and help fungi spread and survive in various environments.
Describe the process of denitrification and its environmental importance.
✔️✔️ Denitrification is the reduction of nitrates to nitrogen gas by bacteria, returning nitrogen to the
atmosphere and completing the nitrogen cycle, which is essential for soil fertility.
How do exotoxins contribute to bacterial pathogenicity?
✔️✔️ Exotoxins are toxic proteins secreted by bacteria that interfere with host cell function, damaging
tissues or disrupting cellular processes, leading to disease symptoms.
Explain the concept of a pathogen's virulence factors.
✔️✔️ Virulence factors are molecules or structures that enhance a pathogen's ability to cause disease,
such as toxins, adhesion proteins, and immune-evasion mechanisms.
Describe the lytic cycle in bacteriophages.
✔️✔️ In the lytic cycle, a bacteriophage attaches to a bacterial cell, injects its DNA, uses the host’s
machinery to replicate and assemble new viruses, then lyses the cell to release them.
What is the significance of Koch's postulates?
✔️✔️ Koch's postulates are a set of criteria to establish a causative relationship between a microbe
and a disease, helping to identify pathogens responsible for specific illnesses.
How does the process of translation contribute to protein synthesis?
✔️✔️ During translation, ribosomes read the mRNA sequence and link amino acids in the correct
order to form a protein, based on the genetic code in the mRNA.
What is the purpose of an anaerobic chamber in microbiology?
✔️✔️ An anaerobic chamber creates an oxygen-free environment, allowing for the growth and study
of anaerobic organisms that cannot survive in the presence of oxygen.
Explain the role of pili in bacterial conjugation.
✔️✔️ Pili are hair-like structures on bacteria that facilitate conjugation by connecting two cells,
allowing the transfer of genetic material, such as plasmids, from one cell to another.
What is the function of catalase in cells?
✔️✔️ Catalase breaks down hydrogen peroxide, a toxic byproduct of cellular metabolism, into water
and oxygen, protecting cells from oxidative damage.
How do vaccines contribute to herd immunity?
✔️✔️ Vaccines reduce the spread of infectious diseases within a population, creating herd immunity
that protects individuals who cannot be vaccinated, such as those with immune deficiencies.
, Describe how binary fission enables bacterial reproduction.
✔️✔️ Binary fission is a process in which a bacterial cell replicates its DNA, elongates, and splits into
two identical daughter cells, allowing for rapid population growth.
What are obligate anaerobes, and where do they typically thrive?
✔️✔️ Obligate anaerobes cannot survive in oxygen and typically thrive in environments like deep soil,
sediments, or the human gastrointestinal tract, where oxygen is absent.
How does the structure of a Gram-positive cell wall differ from a Gram-negative cell wall?
✔️✔️ A Gram-positive cell wall has a thick peptidoglycan layer without an outer membrane, while a
Gram-negative cell wall has a thinner peptidoglycan layer and an outer lipid membrane.
Explain the function of ribosomal RNA (rRNA) in protein synthesis.
✔️✔️ Ribosomal RNA (rRNA) is a structural component of ribosomes that helps facilitate the assembly
of amino acids into proteins, providing a scaffold for translation.
What is the role of spores in fungal reproduction?
✔️✔️ Fungal spores serve as reproductive units, capable of growing into new fungi under favorable
conditions, and help fungi spread and survive in various environments.
Describe the process of denitrification and its environmental importance.
✔️✔️ Denitrification is the reduction of nitrates to nitrogen gas by bacteria, returning nitrogen to the
atmosphere and completing the nitrogen cycle, which is essential for soil fertility.
How do exotoxins contribute to bacterial pathogenicity?
✔️✔️ Exotoxins are toxic proteins secreted by bacteria that interfere with host cell function, damaging
tissues or disrupting cellular processes, leading to disease symptoms.
Explain the concept of a pathogen's virulence factors.
✔️✔️ Virulence factors are molecules or structures that enhance a pathogen's ability to cause disease,
such as toxins, adhesion proteins, and immune-evasion mechanisms.
