What type of immune reaction is most common in identification of vibrio cholerae

Correct Answer: A

Rationale: The correct answer is A: Agglutination. Agglutination is commonly used to identify Vibrio cholerae by clumping together the bacteria with specific antibodies. This reaction occurs when antibodies bind to antigens on the bacterial surface, leading to visible clumps. In contrast, Precipitation, Western blot, and ELISA are not typically used to identify Vibrio cholerae. Precipitation involves antigen-antibody complexes becoming insoluble, Western blot is used for protein detection, and ELISA is commonly used for detecting specific antigens or antibodies in a sample. Agglutination is the most appropriate choice for identifying Vibrio cholerae due to its specific interaction with the bacteria's surface antigens.

Correct Answer: B

Rationale: The correct answer is B: Agglutination reaction. This test is commonly used to detect specific antibodies or antigens. In this case, it can be used to detect plague antigens in the rat tissues or antibodies in the villagers. This test is rapid, sensitive, and can help establish the presence of the causative agent quickly. A: Ring precipitation reaction is not typically used for diagnosing plague and is more commonly used in other types of infections. C: Passive agglutination reaction is not specific for plague and is more commonly used for detecting specific antibodies in diseases like syphilis. D: Neutralization reaction is not typically used for diagnosing plague and is more commonly used to determine the presence of neutralizing antibodies in viral infections.

Correct Answer: A

Rationale: The correct answer is A: emergence. The term emergence refers to the process of a new infectious disease appearing and spreading within a population. It signifies the initial introduction and establishment of the disease in the new population. Explanation for other choices: B: Adoption does not accurately describe the process of a disease spreading within a new population. C: Inclusion is not a term commonly used to describe the spread of infectious diseases. D: Appearance is too vague and does not capture the complexity of the process of establishment and spreading of an infectious disease.

Correct Answer: A

Rationale: The correct answer is A: HIV. HIV is an example of obligate parasitism because it requires a host cell to replicate and survive. It cannot live independently outside of a host organism. In contrast, choices B, C, and D are not obligate parasites. E. Coli and S. Epidermidis are examples of commensal bacteria that can live in the host without causing harm. Pseudomonas aeruginosa can be both an opportunistic pathogen and a free-living organism, not strictly dependent on a host for survival.

Correct Answer: A

Rationale: The correct answer is A: Β-lactamase. In ELISA, enzymes like alkaline phosphatase, horseradish peroxidase, and Β-galactosidase are commonly used as labels to detect the presence of specific molecules. Β-lactamase is not typically used in ELISA as it is an enzyme used to hydrolyze β-lactam antibiotics. Therefore, it does not serve the purpose of detecting specific molecules in ELISA. Alkaline phosphatase, horseradish peroxidase, and Β-galactosidase are preferred enzymes in ELISA due to their ability to produce a detectable signal when bound to specific molecules.

Correct Answer: A

Rationale: The correct answer is A: Metronidazole. Metronidazole is the drug of choice for amebic dysentery as it effectively targets the protozoa causing the infection. It has good tissue penetration and high efficacy against Entamoeba histolytica. Pyrantel (B) is used for nematode infections, not amebiasis. Levamisole (C) is an anthelmintic for roundworms and not effective against amoebas. Bicillin-5 (D) is a penicillin antibiotic, which is not indicated for treating amebic dysentery.

Correct Answer: A

Rationale: The correct answer is A: Blood serum. In suspected cases of brucellosis, blood serum is typically analyzed in a common microbiological laboratory. This is because the bacteria causing brucellosis, Brucella species, can be detected through serological tests in the blood serum. The presence of specific antibodies against Brucella in the serum confirms the diagnosis. Spinal fluid (choice B) would be analyzed in cases of suspected central nervous system infections, which are not typical for brucellosis. Vomit mass (choice C) is not a common sample for microbiological analysis in cases of brucellosis. Urine (choice D) is not the preferred sample for detecting Brucella antibodies; blood serum is the primary choice for serological testing.

Correct Answer: D

Rationale: The correct answer is D: sterols. Eukaryotic cytoplasmic membranes contain sterols, such as cholesterol, which provide stability and regulate fluidity. This is a key characteristic that distinguishes them from prokaryotic membranes. Cellulose (A) is a component of plant cell walls, not the cytoplasmic membrane. Starch (B) is a carbohydrate used for energy storage in plants. Chitin (C) is a component of fungal cell walls and arthropod exoskeletons, not found in eukaryotic cytoplasmic membranes.

Correct Answer: D

Rationale: Rationale: 1. Rickettsiae are obligate intracellular bacteria, hence they do not form spores, capsules, or flagella. 2. They have a slim glycocalyx layer, aiding in attachment to host cells. 3. Bipolar fimbriae are structures that help in adhesion to host cells. Therefore, all statements (A, B, and C) are true for Rickettsiae, making option D the correct answer. Other choices are incorrect as they do not accurately describe the characteristics of Rickettsiae.