MDS PREP
Selective medium for streptococcus mutans?
1 mac conkey medium
2 mitis salivarius bacitracin agar
3 neutrient agar
4 tellurite medium
Microbiology
Answer: 2
Colonies of E. coli serotype O157:H7 appear on Mac Conkey Sorbitol Agar as colourless colonies non-sorbitol fermenter. Others E. coli, sorbitol fermenters, give red colonies and gram-negative non-sorbitol fermenters appear translucent.
The virus which is most resistant to chemical and physical agents is the one which causes
1. infectious hepatitis
2. mumps
3. influenza
4. serum hepatitis
Microbiology
Answer: 4
Infectious hepatitis (Hepatitis A virus): While HAV is
resistant to some environmental conditions, it is generally less resistant
than HBV.
Mumps virus: This is an enveloped virus and is not
particularly resistant to environmental factors.
Influenza virus: This is also an enveloped virus and is
susceptible to heat and many disinfectants.
Serum hepatitis (Hepatitis B virus): HBV is known for
its resilience. It can survive outside the body for long periods and is
resistant to many disinfectants and physical agents, making it one of the
more resistant viruses.
In summary, the correct answer is indeed 4. serum hepatitis
(Hepatitis B virus), as it is more resistant to chemical and physical
agents
What is the primary reservoir for S. typhi?
1) Domestic animals
2) Insects
3) Water and food
4) Human carriers
General Microbiology Answer: 4The primary reservoir for S. typhi is Human carriers: Typhoid fever is primarily a human disease with human carriers serving as the main reservoir for the bacterium. While the bacteria can also be found in water and food, it is typically humans who carry and transmit the infection.
Which of the following bacteriophage types of diphtheria bacilli are associated with avirulent strains?
1) Type I and II
2) Type IV and VI
3) Type III
4) Type VII
Type VII bacteriophage types of diphtheria bacilli are associated with avirulent strains.
Which of the following is considered as a disadvantage in the application of dry heat as a sterilizing agent?
1. Requires excessive time
2. Does not destroy hepatitis viruses
3. Dulls instrument cutting edges
4. All of the above
Microbiology
Answer: 1
Which of the following is a characteristic of amoebic dysentery?
1) More than 10 motions a day
2) Small, odorless stools
3) Dark red, copious stools
4) Presence of Charcot-Leyden crystals
Amoebic dysentery is characterized by more than 10 motions a day and the presence of Charcot-Leyden crystals.
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.
Which of the following hepatitis viruses has a single-stranded RNA genome?
1) Hepatitis A
2) Hepatitis B
3) Hepatitis C
4) Hepatitis D
General Microbiology Answer: 1Hepatitis C virus (HCV) is known for its single-stranded RNA genome. This characteristic is crucial for its classification and understanding its replication cycle, which involves RNA-dependent RNA polymerase.