MDS PREP
What is the typical macroscopic appearance of the stool in cases of amoebic dysentery compared to bacillary dysentery?
1) Amoebic dysentery stool is small and odorless, while bacillary dysentery stool is copious and offensive.
2) Both amoebic and bacillary dysentery stools are copious and offensive.
3) Amoebic dysentery stool is dark red and acidic, while bacillary dysentery stool is bright red and alkaline.
4) Amoebic dysentery stool is bright red and alkaline, while bacillary dysentery stool is dark red and acidic.
General Microbiology Answer: 3
Amoebic dysentery stool is typically dark red and acidic, while bacillary dysentery stool is bright red and alkaline.
Two important factors for initiation of caries by oral streptococci are
1 production of glucosyl transferase and synthesis of insoluble dextran
2. production of acid and production or protease
3. production of collagenase and pro- duct ion of hyaluronidase
4. fermentation of mannitol and sorbitol and production of protease.
Microbiology
Answer: 1
Two important factors for initiation of caries by oral streptococci are production of glucosyl transferase and synthesis of insoluble dextran
What is the typical pH range for optimal growth of meningococci?
1) 6.8-7.0
2) 7.4-7.6
3) 8.0-8.2
4) 7.0-7.2
The optimal pH range for the growth of meningococci is 7.4-7.6.
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
General Microbiology Answer: 3
Amoebic dysentery, caused by the protozoan parasite Entamoeba histolytica, is characterized by the presence of ghost cells in the stool. Ghost cells are the remnants of red blood cells that have been phagocytosed by the amoeba. These cells are ingested and their cytoplasm is removed, leaving only the cell membrane, which gives them a "ghost-like" appearance under the microscope. This feature helps distinguish amoebic dysentery from bacillary dysentery, which is caused by bacteria such as Shigella species. Bacillary dysentery typically shows the presence of white blood cells (pus cells) and red blood cells in the stool, but not ghost cells.
What does the Vi antigen of S. typhi confer upon the bacterium?
1) Resistance to antibiotics
2) Increased invasiveness
3) Resistance to phagocytosis
4) Resistance to acidic environment
General Microbiology Answer: 3the Vi antigen of S. typhi confers upon the bacterium Resistance to phagocytosis. The Vi antigen is a polysaccharide capsule that protects the bacteria from being engulfed and destroyed by phagocytic white blood cells, contributing to its virulence.
The minimum and maximum temperature for normal metabolic
activity microorganisms that live on or within the human body is
1 50 C
to 300 C
2 200 C to 450
C
3. 300 C to 400
C
4. 15 C to 600
C
Microbiology Answer: 2
The minimum and maximum temperature for normal metabolic activity microorganisms that live on or within the human body is 20° C to 45°C
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.
Dry heat sterilization of paper points without incineration is accomplished at
1. 160°C for 2hours
2. 120°C for l hour
3. 100°C for 2 hours
4. 200°C for 1 hour
Microbiology
Answer: 1
Dry heat sterilization of paper points without incineration is accomplished at 160°C for 2hours