Nokea
Which of the following bacteria is responsible for causing gonorrhea?
- A. Chlamydia trachomatis
- B. Neisseria gonorrhoeae
- C. Treponema pallidum
- D. Escherichia coli
Correct Answer: B
Rationale: The correct answer is B: Neisseria gonorrhoeae. This bacterium is responsible for causing gonorrhea. Neisseria gonorrhoeae is a sexually transmitted bacterium that infects the mucous membranes of the reproductive tract. It is known for causing symptoms such as painful urination and discharge. Chlamydia trachomatis (choice A) is another sexually transmitted bacterium but is not responsible for gonorrhea. Treponema pallidum (choice C) causes syphilis, not gonorrhea. Escherichia coli (choice D) is a common bacterium found in the gut and is not associated with causing gonorrhea. Therefore, Neisseria gonorrhoeae is the correct answer for this question.
You may also like to solve these questions
Infectious agents of various ultrastructures can be etiological agents of infectious diseases. Which of the groups named below HAS NO cellular structure, protein synthesizing, enzyme and energy systems?
- A. Viruses
- B. Fungi
- C. Bacteria
- D. Protozoa
Correct Answer: A
Rationale: The correct answer is A: Viruses. Viruses are acellular, meaning they lack cellular structure, protein synthesizing ability, enzymes, and energy systems. They are essentially genetic material (DNA or RNA) enclosed in a protein coat. Fungi (B), bacteria (C), and protozoa (D) are all cellular organisms with protein synthesizing, enzyme, and energy systems. Viruses rely on host cells to replicate and carry out metabolic functions, making them distinct from other groups.
Which of the following statements is FALSE regarding B cells?
- A. B cells that recognize high concentrations of antigen (self) in the absence of other signals undergo apoptosis in the bone marrow
- B. Bone marrow stem cells migrate to the thymus and develop into B cells
- C. B cells synthesize antibodies and put them on their cell surface
- D. B cells can undergo class switching and produce a different antibody type
Correct Answer: B
Rationale: B cells develop in the bone marrow, not the thymus. Firstly, hematopoietic stem cells in the bone marrow give rise to B cells. They undergo maturation and selection processes in the bone marrow, not in the thymus. Therefore, choice B is false. On the other hand, choices A, C, and D are correct. A is true because B cells with high affinity to self-antigens undergo apoptosis to prevent autoimmunity. C is true since B cells synthesize antibodies which can be displayed on their surface as B cell receptors. D is true because B cells can undergo class switching to produce different types of antibodies based on the immune response requirements.
A patient with a sore throat had a throat culture revealing Gram-positive cocci in chains. The bacteria were catalase-negative and beta-hemolytic. What is the most likely causative agent?
- A. Streptococcus pyogenes
- B. Streptococcus pneumoniae
- C. Enterococcus faecalis
- D. Staphylococcus aureus
Correct Answer: A
Rationale: The correct answer is A: Streptococcus pyogenes.
1. Gram-positive cocci in chains suggest streptococci.
2. Catalase-negative indicates it's not staphylococci.
3. Beta-hemolytic points towards Group A Streptococcus (S. pyogenes).
Summary:
B. Streptococcus pneumoniae is not beta-hemolytic.
C. Enterococcus faecalis is not typically chains.
D. Staphylococcus aureus is catalase-positive.
A man died from an acute disease characterized by fever, jaundice, hemorrhagic rash, and acute renal insufficiency. Histological examination revealed spiral bacteria shaped like 'C' and 'S' letters. Identify the pathogen.
- A. Leptospira
- B. Treponema
- C. Borrelia
- D. Spirochaeta
Correct Answer: A
Rationale: The correct answer is A: Leptospira. Leptospira is a spiral-shaped bacterium that causes a disease known as leptospirosis, characterized by fever, jajsondice, hemorrhagic rash, and renal insufficiency. The characteristic spiral shape of the bacteria, resembling 'C' and 'S' letters, is a key identifying feature. Leptospira is commonly associated with contaminated water sources and can be transmitted to humans through contact with infected animals or water.
Summary of other choices:
B: Treponema - Treponema pallidum is the causative agent of syphilis, which does not typically present with the combination of symptoms described in the question.
C: Borrelia - Borrelia species are associated with Lyme disease and relapsing fever, but do not match the specific symptoms and histological appearance described in the question.
D: Spirochaeta - Spirochaeta is a genus of bacteria, but specific species within
Which of the following viral infections can result in chronic carrier state.
- A. HBV
- B. HCV
- C. HDV
- D. All of these
Correct Answer: D
Rationale: The correct answer is D: All of these. HBV, HCV, and HDV can all lead to chronic carrier states due to their ability to establish persistent infections in the liver. HBV can result in chronic hepatitis, cirrhosis, and even liver cancer. HCV can also lead to chronic hepatitis and liver damage. HDV is a defective virus that requires HBV for replication and can worsen the outcome of HBV infection, potentially leading to chronic liver disease. Therefore, all three viruses have the potential to cause chronic carrier states.