Quiz on Nitrogen Metabolism in Dental Biofilm

What is the main source of nitrogen in dental plaque?

• Lactic acid

• Sodium chloride

• Glucose

• Salivary urea

Which bacteria are known for high urease activity in dental plaque?

• Escherichia coli

• Actinomyces naeslundii

• Staphylococcus aureus

• Lactobacillus casei

What role does ammonia play in the oral environment?

• Decreases plaque pH

• Increases plaque pH

• Promotes enamel demineralization

• Inhibits bacterial growth

What is the function of salivary peptides like sialin?

• Promote protein degradation

• Modulate bacterial metabolism

• Increase acidity

• Inhibit urea breakdown

Which amino acid is converted into ammonia via the arginine deiminase system?

• Cysteine

• Arginine

• Lysine

• Glutamate

What is a harmful effect of ammonia in periodontal tissues?

• Enhances nutrient absorption

• Promotes tissue healing

• Increases tissue permeability

• Reduces inflammation

What type of bacteria primarily utilize gingival crevicular fluid in periodontal pockets?

• Saccharolytic bacteria

• Aerobic bacteria

• Anaerobic bacteria

• Asaccharolytic bacteria

Which enzyme breaks down collagen in periodontal tissues?

• Amylase

• Chondroitin sulfatase

• Collagenase

• Hyaluronidase

What is the effect of nitric oxide in the oral cavity?

• Suppresses acid-forming bacteria

• Decreases immune response

• Increases acidity

• Promotes bacterial growth

What is the primary function of bacterial decarboxylase at low pH?

• Break down carbohydrates

• Synthesize proteins

• Increase acidity

• Produce ammonia