MDS PREP
Which of the following is a characteristic of endotoxins that makes them distinct from exotoxins?
1) They are heat labile
2) They are actively secreted by bacterial cells
3) They are proteins
4) They are part of the bacterial cell wall
General Microbiology Answer: 4
Endotoxins are components of the outer membrane of Gram-negative bacteria and are released when the bacteria die or divide. This structural characteristic differentiates them from exotoxins, which are secreted by living bacteria.
What is the correct color coding for bio-medical waste that requires incineration or deep burial?
1) Red
2) Yellow
3) Blue/white translucent
4) Black
General Microbiology Answer: 2
Yellow is the designated color for bio-medical waste that is considered hazardous and requires incineration or deep burial. This classification helps in the proper disposal of infectious and potentially harmful materials.
Which of the following statements is true about the colony morphology and cultural characteristics of Anthrax bacilli?
1) Anthrax bacilli are motile and produce a turbidity in broth.
2) The Medusa head appearance is seen in non-virulent strains of anthrax bacilli.
3) Virulent capsulated strains form smooth colonies.
4) The inverted fir tree appearance is characteristic of Anthracoid bacilli.
The Medusa head appearance is characteristic of virulent strains of anthrax bacilli, not non-virulent strains.
What is the significance of HLA class I antigens in the context of graft rejection and cell mediated cytolysis?
1) They are only involved in cell-to-cell recognition in the immune system.
2) They are the principal antigens that induce an immune response in the host against transplanted tissues.
3) They have no role in graft rejection or cell-mediated immunity.
4) They are only involved in the innate immune response.
HLA class I antigens are the principal antigens that induce an immune response in the host against transplanted tissues.
Which of the following is a killed viral vaccine?
1) Sabin vaccine for poliomyelitis
2) Salk vaccine for poliomyelitis
3) MMR vaccine for measles, mumps, rubella
4) Varicella-zoster
General Microbiology Answer: 2
The Salk vaccine for poliomyelitis is a killed viral vaccine, effectively preventing the disease by using inactivated poliovirus.
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.
What are the typical clinical features of typhoid fever?
1) High fever, bradycardia, and a palpable spleen
2) Rash, joint pain, and respiratory symptoms
3) Diarrhea, abdominal cramps, and vomiting
4) Headache, photophobia, and neck stiffness
General Microbiology Answer: 1The typical clinical features of typhoid fever can be listed as follows:
1. High fever, bradycardia, and a palpable spleen: Typhoid fever is
characterized by a sustained high fever, often reaching 103°F to 104°F (39°C to
40°C). Bradycardia, or a slower than normal heart rate, occurs in some cases.
The spleen may also become enlarged and palpable due to the infection.
2. Rash, joint pain, and respiratory symptoms: Some patients may develop a rash
known as "Rose spots," which are small, red spots on the abdomen and chest.
Joint pain can occur, and respiratory symptoms may include a dry cough.
3. Diarrhea, abdominal cramps, and vomiting: Diarrhea and severe abdominal
cramps are common in the early stages of typhoid fever, which can lead to
significant dehydration and discomfort for the patient.
4. Headache, photophobia, and neck stiffness: Headaches and sensitivity to light
(photophobia) are often present, and in severe cases, neck stiffness can occur
due to inflammation of the meninges, known as meningitis.
What is the primary cause of cutaneous anthrax?
1) Inhalation of spores
2) Entry through the skin
3) Ingestion of contaminated food
4) Contact with infected animals
Cutaneous anthrax is primarily caused by entry through the skin, often through abrasions or cuts.