Module 9 12 Part 4 Flashcards
Question
Answer
Q: How do genetic changes in the microbial genome lead to drug resistance?
A: Genetic changes in the microbial genome can result in structural and functional alterations that lead to drug resistance.
Q: What are the two main ways in which these genetic changes can occur?
A: Genetic changes can happen through either spontaneous mutations within the microbe or by acquiring DNA from an external source.
Q: What is conjugation, and how does it relate to the acquisition of DNA for drug resistance?
A: Conjugation is a mechanism by which bacteria can acquire DNA from other bacteria. This process enables the transfer of resistance genes and plays a significant role in the development of drug resistance.
Q: What are spontaneous mutations in microbes, and how do they affect drug resistance?
A: Spontaneous mutations are random changes in a microbe’s DNA that gradually increase drug resistance, starting with low-level resistance and potentially increasing with more mutations.
Q: Can spontaneous mutations confer resistance to multiple drugs, or is it typically limited to one drug?
A: Spontaneous mutations generally provide resistance to only one specific drug.
Q: What is conjugation, and what does it involve?
A: Conjugation is a process where extrachromosomal DNA is transferred from one bacterium to another.
Q: How is drug resistance transferred through conjugation, and what are the requirements for the donor bacterium?
A: Drug resistance is transferred via conjugation when the donor bacterium possesses two separate DNA segments: one containing the genes for drug resistance mechanisms and another with genes for the “sexual” apparatus necessary for DNA transfer. These two segments together make up an R factor, or resistance factor.
Q: Among which type of bacteria does conjugation primarily occur?
A: Conjugation is mainly observed among gram-negative bacteria.
Q: Can genetic material be transferred between different bacterial species through conjugation?
A: Yes, genetic material can be transferred between bacteria of the same species or between different species.
Q: Is the transfer of R factors species-specific, and what are the implications of this?
A: The transfer of R factors is not species-specific, meaning that pathogenic bacteria can potentially acquire resistance genes from the normal bacterial flora in the body.
Q: Why is the increasing presence of R factors in the normal flora a significant clinical concern?
A: The growing prevalence of R factors in normal flora raises concerns about the potential transfer of antibiotic resistance from normal flora bacteria to pathogenic bacteria, impacting clinical outcomes.
Q: How does conjugation differ from spontaneous mutation in terms of drug resistance?
A: Conjugation frequently confers resistance to multiple drugs, while spontaneous mutation usually provides resistance to a single drug.
Q: What enables conjugation to confer resistance to multiple drugs in a single event?
A: Conjugation can transfer DNA that contains genes for various drug-metabolizing enzymes, allowing a bacterium to acquire resistance to multiple drugs simultaneously.
Q: How does antibiotic use relate to the emergence of drug-resistant microbes?
A: Antibiotic use promotes the development of drug-resistant microbes.
Q: Do antibiotics directly cause genetic changes that lead to reduced drug sensitivity?
A: No, antibiotics are not mutagenic and do not directly cause genetic changes resulting in reduced drug sensitivity.
Q: What are the main factors responsible for the development of drug resistance in microbes?
A: Spontaneous mutations and conjugation are the primary factors leading to drug resistance, and they are random events unrelated to antibiotic use.
Q: What role do antibiotics play in the development of drug resistance?
A: Antibiotics create conditions that support the overgrowth of microbes that have acquired resistance mechanisms.
Q: Do all antimicrobial drugs play a role in the emergence of drug-resistant organisms?
A: Yes, all antimicrobial drugs contribute to the development of drug-resistant organisms.
Q: What distinguishes some agents from others in their potential to promote resistance?
A: Certain agents are more likely to promote resistance than others.
Q: Why are broad-spectrum antibiotics more likely to facilitate the emergence of resistance?
A: Broad-spectrum antibiotics target a wide range of bacteria and can kill a larger number of competing organisms, which increases their potential to promote resistance.
Q: How does the impact of broad-spectrum antibiotics compare to that of narrow-spectrum drugs in terms of resistance development?
A: Broad-spectrum antibiotics have a greater potential to promote the emergence of drug-resistant organisms compared to narrow-spectrum drugs.
Q: What is the relationship between the use of antibiotics and the emergence of drug-resistant organisms?
A: Increased use of antibiotics accelerates the emergence of drug-resistant organisms.
Q: How do antibiotics affect both resistant pathogens and normal flora?
A: Antibiotics promote the emergence of resistant pathogens and overgrowth of normal flora with resistance mechanisms.
