S.I. And Unit Quiz Questions Flashcards
What is NOT a method os microbial control that is used outside of the body
Sterilization
Sepsis
Disinfection
Decontamination
Sepsis
T/F: the goal of any sterilization process is the destruction of bacterial endospores
True
What is an agent that uses chemicals that destroys bacteria except for those in the endospores stage
Bactericide
What uses a chemical agent that kills microorganisms
Germicide/microbicide
What is it called when there is a growth of microorganisms in the blood and other tissues?
Sepsis
What is not an influence on the action of antimicrobial agents?
All of the above can
- temperature and PH
- the concentration of the agent
- the mode of the action of the agent
- the presence of solvents, inhibitor, or interfering organic matter
A chemical agent that dissolves in lipids can damage
Cells and enveloped viruses
Aseptic means?
Free of pathogens
Methods of microbial control called ——— arrest the growth of microbes
Germistatic
Seventy percent alcohol is effective against?
Enveloped viruses
Silvadene, a topical treatment for burns, contains 1% silver. What category of chemical control agent is in Silvadene?
Heavy metals
Washing dishes in the dishwasher with detergent and hot water is a ——— process
Degerming and disinfecting
Which is the most difficult to inactivate?
- enveloped viruses
- protozoan cysts
- bacterial endospores
- nonenveloped viruses
- fungus spores
Bacterial endospores
Which of the following statements is TRUE of disinfectants?
- used for sterilization
- used on living tissues
- only effective for short periods of time
- effective for destroying endospores
- used on inanimate surfaces
Used on inanimate surfaces
You notice a sign in a public restroom that states “Sanitized for your safety”. This means what?
Methods of infection that meet the minimum standard of microbial removal have been used
Characteristics of the ideal antimicrobial drug
- toxic to the microbe but not the host cell
- relatively soluble: functions even when highly diluted in body fluids
- remains potent for long enough to act and is not broken down or excreted prematurely
- does not lead to development of antimicrobial resistance
- doesn’t disrupt the hosts health by causing allergies or predisposing the host to another infection
Ways antibiotics kill bacteria
1) target cell wall
-
-
2) target protein synthesis
-
- tetracycline
3) target folic acid synthesis
- nucleic acid synthesis
- sulfamethoxazole
4) target DNA or RNA
- inhibit DNA unwinding enzymes of helicases
- levofloxacin
5) targets cytoplasmic or cell membranes
- polymyxin B
How does resistance develop
1) spontaneous mutations in critical chromosomal genes
2)
3) slowing or stopping metabolism so that the microbe cannot be harmed by he antibiotic
A) do not grow, do not die
B) dormant
C) tolerant of antibiotics
Serial dilutions
- a stepwise series of dilutions of a substance
- the point is to reduce the concentration to a more usable concentration
- it is irrelevant if there are so many that you simply can not count the colonies
Microbiome
- made up of good bacteria
- can block pathogens form growing our - microbiome will be using up all of the nutrients so the pathogens will not have any available to them
- some bacteria in our but will use enzymes to break down our ingested food more than our bodies can on their own
- some of the bacteria that you find in your gut is not the same as the bacteria on skin
- probiotics help to reestablish gut microbiomes
Modes of transmission
- direct contact
- body contact between hosts
- Mono -> Epstein-Barr virus -> kissing disease
- indirect contact
- pathogens are spread from host to host by fomites
- objects that are likely to carry infection
- STIs and Salmonella
- fomites include tables, door handles, and clothing
- droplet
- spread of pathogens in droplets of mucus by exhaling, coughing, and sneezing
Mode of transmission - vehicle
Airborne
- aerosols
Waterborne
- pathogen is in the water (GI diseases)
Food borne
- antibiotic resistance
Bodily fluid
- blood, urine, etc
Mode of transmission - vector
Vector: A carrier of a disease - causing agent from un infected individual to a non-infected individual or its parts
- West Nile Virus -> spread by mosquitos
- not human to human spread
Mosquitos, fleas, ticks, lice, and flies
Imipenem mode of action
inhibits cross-linking of peptidoglycan during cell wall synthesis by inactivating penicillin binding proteins
What is a medication that inhibits synthesis of ergosterol that would be effective in treatment
- mycobacterial disease
- bacterial infections
- viral disease
- fungal infections
- Protozoa infections
- fungal infections
Beta-lactam antibiotics have an effect on which of the following types of cells?
- bacterial cells
- virus-infected cells
- animal cells
- fungal cells
- both animal and fungal cells
- bacterial cells
Drug-resistant populations of microbes arise when ————
- exposure to drugs selectively kills sensitive cells, allowing overgrowth of resistant cells
Infection of the ——— would be the hardest to treat with antimicrobial drugs
- brain