MDS PREP
What is the characteristic odor of cultures of proteus bacilli?
1) Fruity
2) Fishy or seminal
3) Sweet
4) Foul
General Microbiology Answer: 2Proteus bacilli are known for their characteristic swarming motility on agar and a distinctive odor, which is often described as fishy or seminal. This is due to the production of ammonia and indole as metabolic byproducts.
In concentrations usually applied for sterilization purposes, ethylene oxide is preferable to formaldehyde becuase it is
1. more readily polymerized to an active form
2. less toxic
3. less likely to form an explosive mixture with air
4. more penetrating
Microbiology
Answer: 4
In concentrations usually applied for sterilization purposes, ethylene oxide is preferable to formaldehyde becuase it is more penetrating
What is a characteristic feature of Streptococcus viridans?
1) Capsulated, oval-shaped cells
2) Non-capsulated, round to oval cells in chains
3) Positive oxidase reaction
4) Negative oxidase reaction
Streptococcus viridans is characterized by non-capsulated, round to oval cells in chains and has a negative oxidase reaction.
What is the significance of "Rose spots" in typhoid fever?
1) They indicate the presence of a complication such as intestinal perforation.
2) They are a diagnostic sign of typhoid fever.
3) They indicate the patient is no longer infectious.
4) They indicate the patient has developed antibodies to the bacterium.
General Microbiology Answer: 2The presence of "Rose spots" can
help in diagnosing typhoid fever, as they are relatively specific to this
illness. They typically appear in the trunk and are not a result of increased
sensitivity to the touch or pressure.
Which of the following is a distinguishing feature of exotoxins?
1) Lipopolysaccharides
2) Heat stable
3) Actively secreted by cells
4) Obtained only by cell lysis
General Microbiology Answer: 3
Exotoxins are produced and secreted by bacteria into the surrounding environment. They are typically proteins that can cause damage to the host by disrupting cellular processes. This active secretion distinguishes them from endotoxins, which are part of the bacterial cell wall and are released upon cell lysis.
The period from disease initiation to disease detection in non-infectious disease is called -
1. Incubation period
2. Serial interval
3. Latent period
4. Lag time
Microbiology
Answer: 3
Incubation period: This term is typically used for
infectious diseases and refers to the time between exposure to the
infectious agent and the onset of symptoms.
Serial interval: This refers to the time between
successive cases in a chain of transmission, specifically in infectious
diseases.
Latent period: This is the time from the initiation of
the disease process (or exposure to a risk factor) until the disease is
detectable or until symptoms appear. In non-infectious diseases, this period
can be significant, as the disease may be developing without any noticeable
symptoms.
Lag time: This term can refer to various delays in
processes but is not specifically defined in the context of disease
initiation and detection.
Which of the following is a characteristic microscopic feature of amoebic dysentery that distinguishes it from bacillary dysentery?
1) Presence of RBCs in the stool
2) Presence of pus cells in the stool
3) Presence of Charcot-Leyden crystals
4) Presence of ghost cells
The presence of Charcot-Leyden crystals is a characteristic microscopic feature of amoebic dysentery that distinguishes it from bacillary dysentery.
What is the purpose of the puncture-proof container in bio-medical waste management?
1) To contain sharps
2) To hold non-infectious waste
3) To store chemicals used for disinfection
4) To transport pathological waste
General Microbiology Answer: 1
The purpose of the puncture-proof container in bio-medical waste management is to contain sharps, preventing injuries and contamination.