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What is the primary medium used to culture a nasopharyngeal swab for diagnosing Neisseria meningitidis carriers?
What is the primary medium used to culture a nasopharyngeal swab for diagnosing Neisseria meningitidis carriers?
Gram-negative cocci can only appear in pairs.
Gram-negative cocci can only appear in pairs.
False
Name one serious infection caused by Gram-negative cocci.
Name one serious infection caused by Gram-negative cocci.
Gonorrhea or meningitis
Gram-negative cocci typically appear as _____ shaped bacterial cells under the microscope.
Gram-negative cocci typically appear as _____ shaped bacterial cells under the microscope.
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Match the following Gram-negative cocci with their associated disease:
Match the following Gram-negative cocci with their associated disease:
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What characteristic staining property do Gram-negative cocci exhibit?
What characteristic staining property do Gram-negative cocci exhibit?
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Gram-negative cocci can be found in various natural environments.
Gram-negative cocci can be found in various natural environments.
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Which of the following is a key pathogenic Neisseria species responsible for gonorrhea?
Which of the following is a key pathogenic Neisseria species responsible for gonorrhea?
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Neisseria species are typically Gram-positive cocci.
Neisseria species are typically Gram-positive cocci.
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What is the shape commonly used to describe Neisseria species?
What is the shape commonly used to describe Neisseria species?
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Neisseria species require _______ media like blood agar for optimal growth.
Neisseria species require _______ media like blood agar for optimal growth.
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Match the Neisseria species with their disease association:
Match the Neisseria species with their disease association:
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Which of the following is NOT a virulence factor of Neisseria species?
Which of the following is NOT a virulence factor of Neisseria species?
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CSF used for microbiological analysis typically contains exclusively lymphocytes.
CSF used for microbiological analysis typically contains exclusively lymphocytes.
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What is one method used to diagnose Neisseria meningitidis?
What is one method used to diagnose Neisseria meningitidis?
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CSF for protein and glucose analysis is collected in tube ______.
CSF for protein and glucose analysis is collected in tube ______.
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Which of the following statements accurately describes gram-negative cocci?
Which of the following statements accurately describes gram-negative cocci?
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Gram-negative cocci appear pink or red when subjected to Gram staining.
Gram-negative cocci appear pink or red when subjected to Gram staining.
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Name one species of medically important gram-negative cocci.
Name one species of medically important gram-negative cocci.
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Gram-negative cocci typically grow well on __________ agar.
Gram-negative cocci typically grow well on __________ agar.
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Which media is used specifically to isolate and differentiate specific Gram-negative cocci species?
Which media is used specifically to isolate and differentiate specific Gram-negative cocci species?
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Oxidase test is performed to determine the ability of bacteria to ferment carbohydrates.
Oxidase test is performed to determine the ability of bacteria to ferment carbohydrates.
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What incubation temperature range is typically required for gram-negative cocci?
What incubation temperature range is typically required for gram-negative cocci?
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Which test is NOT typically performed to confirm the species identification of Neisseria?
Which test is NOT typically performed to confirm the species identification of Neisseria?
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Match the following gram-negative cocci species with their respective infections:
Match the following gram-negative cocci species with their respective infections:
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What color do gram-negative cocci appear when subjected to Gram staining?
What color do gram-negative cocci appear when subjected to Gram staining?
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Gram-negative cocci require anaerobic conditions for optimal growth.
Gram-negative cocci require anaerobic conditions for optimal growth.
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Name one pathogen related to the genus Neisseria.
Name one pathogen related to the genus Neisseria.
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Match the following biochemical tests with their purpose:
Match the following biochemical tests with their purpose:
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What is a key virulence factor of Neisseria species?
What is a key virulence factor of Neisseria species?
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Neisseria meningitidis can be diagnosed by collecting samples from the nasopharynx or cerebrospinal fluid.
Neisseria meningitidis can be diagnosed by collecting samples from the nasopharynx or cerebrospinal fluid.
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What appearance do Neisseria species commonly exhibit under a microscope?
What appearance do Neisseria species commonly exhibit under a microscope?
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Neisseria species require _______ media for optimal growth.
Neisseria species require _______ media for optimal growth.
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Match the following Neisseria species with their associated diseases:
Match the following Neisseria species with their associated diseases:
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Which species is known to cause meningitis?
Which species is known to cause meningitis?
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Gram-negative cocci have a thick peptidoglycan layer in their cell wall.
Gram-negative cocci have a thick peptidoglycan layer in their cell wall.
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Name one morphological feature of Gram-negative cocci.
Name one morphological feature of Gram-negative cocci.
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Gram-negative cocci are often identified by their characteristic _______ appearance, resembling a coffee bean.
Gram-negative cocci are often identified by their characteristic _______ appearance, resembling a coffee bean.
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Match each Gram-negative cocci species with their associated infection:
Match each Gram-negative cocci species with their associated infection:
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Study Notes
Gram-Negative Cocci: Medically Relevant Diagnosis
- Gram-negative cocci are spherical bacteria that stain pink or red in Gram staining.
- They have a thin peptidoglycan layer and an outer membrane.
- They can appear in pairs (diplococci), tetrads, or irregular clusters.
- This morphological variability helps in species identification.
- Gram-negative cocci are fastidious and require specialized culture media and growth conditions for optimal growth in the laboratory.
- Thayer-Martin medium is a selective medium used to cultivate Neisseria species.
- Common species include Neisseria gonorrhoeae and Neisseria meningitidis, responsible for gonorrhea and meningitis, respectively.
- Moraxella catarrhalis causes respiratory infections.
- Acinetobacter baumannii produces multidrug-resistant infections.
- Neisseria species are usually Gram-negative diplococci, often described as coffee bean-shaped.
- Neisseria species are typically grown on enriched media like blood agar or chocolate agar and require 5-10% CO2.
- Key pathogenic species include Neisseria gonorrhoeae which is the causative agent of gonorrhea and Neisseria meningitidis which is responsible for causing meningococcal disease.
- Neisseria species are characterized by Pili, outer membrane proteins, and capsular polysaccharides.
- Methods for diagnosing Neisseria meningitidis include sample collection from nasopharynx or cerebrospinal fluid (CSF), Gram staining to observe characteristic Gram-negative diplococci, and culture-based identification using selective media like modified Thayer-Martin agar and biochemical tests.
- CSF for microbiological analysis typically includes numerous polymorphs.
- Neisseria gonorrhoeae is identified through culture on Thayer-Martin medium to distinguish it from other bacteria which may show overgrowth when grown on chocolate agar.
- The oxidase test identifies bacteria that produce cytochrome c oxidase, helping differentiate between Gram-negative groups. Oxidase-positive bacteria include Neisseria, Pseudomonas, and Vibrio.
- Neisseria gonorrhoeae do not grow on blood agar.
- Moraxella catarrhalis culture grows well on blood agar or chocolate agar, exhibiting smooth, grayish, and non-hemolytic colonies.
- Moraxella catarrhalis is characterized by Gram-negative diplococci, with a 'coffee bean' morphology under the microscope.
- Moraxella catarrhalis is identified using biochemical tests including catalase, oxidase, and DNase tests.
- Gonorrhea is sexually transmitted.
- The mode of transmission of Neisseria meningitidis is droplets.
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Description
Test your knowledge about the medically relevant Gram-negative cocci. This quiz covers their identification, growth conditions, and the diseases they cause. Enhance your understanding of bacteria such as Neisseria and Moraxella through this focused assessment.
