Introduction to Microbiology
Labset Four Worksheet
1. Define the term “selectively toxic.” Why is it an important feature of antimicrobial agents? A substance or drug is selectively toxic if the agent used in it is able to kill the microorganism that it is meant to without harm to the host that has taken the drug. This is very important to microbial agents in that it enables these agents to inhibit a microorganism by interacting with microbial functions or structures different from those of the host; thereby showing little or no effect to the host.
2. What are broad and narrow spectrum antimicrobials? What are the pros and cons of each?
Broad spectrum antibiotics work against many types of organisms such as gram positives, gram negatives and anaerobes. The great thing about this is that these are prescribed empirically so that all potential bacteria are covered until the culture results return. The problem with the misuse of broad spectrums is the resistance it can cause. The good thing about the narrow spectrum is that it covers for the specific organism that is causing the infection. The problem is that treatment for the wrong organism can occur.
3. What are some common mechanisms by which antimicrobial resistance emerges?
Some common mechanisms by which antimicrobial resistance emerges are incomplete dosing where the bacteria adapts, random mutations that are beneficial are conserved in the species, previous exposure to antibiotics, and some bacteria are naturally transformable; meaning they can absorb the genomic material of other bacteria into their own.
4. What is a fomite?
A fomite is an inanimate object (as a dish, toy, book, doorknob, or clothing) that may be contaminated with infectious organisms and serve in their
1. Define the term “selectively toxic.” Why is it an important feature of antimicrobial agents? A substance or drug is selectively toxic if the agent used in it is able to kill the microorganism that it is meant to without harm to the host that has taken the drug. This is very important to microbial agents in that it enables these agents to inhibit a microorganism by interacting with microbial functions or structures different from those of the host; thereby showing little or no effect to the host.
2. What are broad and narrow spectrum antimicrobials? What are the pros and cons of each?
Broad spectrum antibiotics work against many types of organisms such as gram positives, gram negatives and anaerobes. The great thing about this is that these are prescribed empirically so that all potential bacteria are covered until the culture results return. The problem with the misuse of broad spectrums is the resistance it can cause. The good thing about the narrow spectrum is that it covers for the specific organism that is causing the infection. The problem is that treatment for the wrong organism can occur.
3. What are some common mechanisms by which antimicrobial resistance emerges?
Some common mechanisms by which antimicrobial resistance emerges are incomplete dosing where the bacteria adapts, random mutations that are beneficial are conserved in the species, previous exposure to antibiotics, and some bacteria are naturally transformable; meaning they can absorb the genomic material of other bacteria into their own.
4. What is a fomite?
A fomite is an inanimate object (as a dish, toy, book, doorknob, or clothing) that may be contaminated with infectious organisms and serve in their