Nokea
Bacteriological examination of the urine of the patient with pyelonephritis revealed microorganisms that produced yellow-green pigment and a characteristic odor in meat-peptone agar. What are they called?
- A. Pseudomonas B.Escherichia C.Proteus D.Klebsiella E.Azotobacter
Correct Answer: A
Rationale: The correct answer is A: Pseudomonas. Pseudomonas bacteria are known to produce yellow-green pigment and a characteristic odor, specifically in meat-peptone agar. This is due to the production of pyoverdin pigment by Pseudomonas. Other choices like Escherichia, Proteus, Klebsiella, and Azotobacter do not typically produce yellow-green pigment or have a characteristic odor in meat-peptone agar. Therefore, based on the specific characteristics mentioned in the question, Pseudomonas is the most appropriate choice.
You may also like to solve these questions
A patient diagnosed with botulism has been prescribed antibotulinic serum for treatment. What immunity will be formed in the given patient?
- A. Antitoxic passive immunity
- B. Infection immunity
- C. Antitoxic active immunity
- D. Antimicrobic active immunity
Correct Answer: A
Rationale: The correct answer is A: Antitoxic passive immunity. Antibotulinic serum contains pre-formed antibodies against the botulinum toxin, providing immediate protection to the patient. This is passive immunity as the patient does not produce their antibodies but receives them externally. Choice B is incorrect as botulism is not an infection, so the patient does not develop infection immunity. Choice C is incorrect because active immunity involves the body producing its antibodies after exposure to an antigen, which is not the case here. Choice D is incorrect as antimicrobic immunity relates to protection against microbes, not toxins like in botulism.
The technique that combines freezing and drying to preserve microbes and other cells is
- A. desiccation.
- B. lyophilization.
- C. pasteurization.
- D. radiation.
Correct Answer: B
Rationale: The correct answer is B: lyophilization. This technique involves freezing the sample and then removing the ice through sublimation, preserving the cells in a dry state. Desiccation (A) simply involves drying without freezing. Pasteurization (C) is a heat treatment to kill pathogens, not used for preservation. Radiation (D) can sterilize but doesn't involve freezing and drying like lyophilization.
Which of the following(s) is/are the determinants of antigenicity?
- A. Chemical nature
- B. Size of the antigen
- C. Foreign origin
- D. All of these
Correct Answer: D
Rationale: The correct answer is D, as all options A, B, and C are determinants of antigenicity.
A: Chemical nature influences how the immune system recognizes antigens.
B: The size of the antigen affects its ability to be recognized by immune cells.
C: Antigens of foreign origin are more likely to trigger an immune response.
Therefore, all of these factors together play a crucial role in determining antigenicity.
In a bacteriology lab, bacteria cultured from fecal samples produced red colonies on Endo agar. What is the most likely microorganism?
- A. Escherichia coli
- B. Salmonella
- C. Shigella
- D. Proteus vulgaris
Correct Answer: A
Rationale: The correct answer is A: Escherichia coli. E. coli typically produces red colonies on Endo agar due to its ability to ferment lactose. This results in the production of acid, causing the colonies to appear red. Salmonella and Shigella are non-lactose fermenters, so they would appear colorless or transparent on Endo agar. Proteus vulgaris is not commonly associated with red colonies on Endo agar. Therefore, based on the characteristic lactose fermentation pattern, E. coli is the most likely microorganism in this scenario.
Extrachromosomal carriers of the genetic information in bacteria are:
- A. Mesosomes
- B. Plasmids
- C. Ribosomes
- D. None of the above
Correct Answer: B
Rationale: The correct answer is B: Plasmids. Plasmids are extrachromosomal DNA molecules found in bacteria that can replicate independently of the bacterial chromosome. They carry additional genetic information, such as antibiotic resistance genes or virulence factors. Mesosomes (choice A) are not involved in carrying genetic information; they are infoldings of the cell membrane. Ribosomes (choice C) are cellular organelles responsible for protein synthesis, not carriers of genetic information. Choice D is incorrect as plasmids are indeed extrachromosomal carriers of genetic information in bacteria.