Microbiology Quiz

What is the main reason for the extreme resistance of bacterial endospores?

• High water content

• High metabolic activity

• High permeability of spore wall

• Low water content

Which shape is described as a rod or bacillus?

• Coccus

• Spirillum

• Vibrio

• Bacillus

What is the optimum pH range for neutrophiles?

• Below 5.5

• 5 to 8

• Above 8.5

• Above 11

At what temperature range do thermophiles grow best?

• -5°C to 15°C

• 25°C to 45°C

• 45°C to 70°C

• 70°C to 110°C

During which phase of growth do bacteria synthesize RNA, enzymes, and essential metabolites?

• Lag phase

• Logarithmic phase

• Stationary phase

• Death phase

What is the primary energy source for chemotrophs?

• Light

• Chemical compounds

• Organic compounds

• Inorganic compounds

Which type of bacteria grow best at moderate temperatures?

• Thermophiles

• Mesophiles

• Psychrophiles

• Hyperthermophiles

What is the water activity range that most bacteria require for growth?

• Above 0.85

• 0.7 to 0.85

• 0.5 to 0.7

• Below 0.5

Which type of bacteria reproduce asexually through binary fission?

• Fungi

• Algae

• Protozoa

• Bacteria

What is the main function of superoxide dismutase enzyme in bacteria?

• Breaks down urea

• Converts hydrogen peroxide to water and oxygen

• Neutralizes singlet oxygen

• Converts superoxide to hydrogen peroxide