MDS PREP
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.
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.
Which of the following is NOT a characteristic of anthracoid bacilli?
1) Generally motile
2) Non-capsulated
3) Grow in long chains
4) Pathogenic to laboratory animals
Anthracoid bacilli are generally non-motile and non-capsulated, and they do not grow in long chains.
What is the effect of Actinomycin D on orthomyxoviruses?
1) Stimulates multiplication
2) Inhibits multiplication
3) No effect
4) Enhances stability
General Microbiology Answer: 2Actinomycin D is an antibiotic that inhibits RNA synthesis. In the case of orthomyxoviruses, it effectively inhibits their multiplication by preventing the transcription of viral RNA, thereby blocking the virus ability to replicate. Actinomycin D inhibits the multiplication of orthomyxoviruses by blocking RNA synthesis, which is crucial for viral replication.
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.
The most efficient method of sterilization in dental practice is
1. ultraviolet radiation
2. moist heat at 121°C for 20 min
3. boiling for 20 mm
4. dry heat at 40° C for 2 hours
Microbiology
Answer: 2
The most efficient method of sterilization in dental practice is moist heat at 121°C for 20 min
What type of antibodies are known as "coproantibodies"?
1) IgA
2) IgM
3) IgG
4) Antibodies found in feces
General Microbiology Answer: 4Copro antibodies are antibodies found in feces These are typically IgA antibodies that are produced in response to infections in the gastrointestinal tract, including typhoid fever. They can be detected in stool samples and are used in diagnostic tests.
Which of the following is an acidogenic genus found in deep dental caries, that often increases significantly in
the saliva during periods of caries activity?
1.Lactobacillus
2.Candida
3. Actinomyces
4. Rothia
Microbiology
Answer: 1
Lactobacillus is an acidogenic genus found in deep dental caries, that often increases significantly in
the saliva during periods of caries activity