B. Microbial Growth Quiz

What are biofilms?

• Microbes that grow attached to surfaces

• Microbes that grow in isolation

• Microbes that float freely in water

• Microbes that grow in extreme temperatures

What is the function of extracellular polymeric substance (EPS) in biofilm formation?

• To regulate temperature within the biofilm

• To provide nutrients to the microbes

• To protect microbes from harmful agents

• To inhibit microbial growth

What is the process by which bacterial cells in biofilms communicate?

• Quorum sensing

• Osmosis

• Photosynthesis

• Respiration

What are extremophiles?

• Microbes that grow in moderate environmental conditions

• Microbes that grow in harsh conditions

• Microbes that require high oxygen levels

• Microbes that prefer low temperatures

What is the effect of a hypotonic solution on microbial cells?

• Cells shrink and may burst

• Cells swell and may burst

• Cells remain unaffected

• Cells become dormant

What is the optimal pH range for acidophiles?

• 8.5-11.5

• 5.5-7

• 0-5.5

• Above 11.5

Which type of microorganism requires salt concentrations of 2M to 6.2M for growth?

• Thermophiles

• Alkaliphiles

• Acidophiles

• Halophiles

What is the temperature range for psychrophiles?

• 0°C to 20°C

• 20°C to 45°C

• 85°C to 113°C

• 55°C to 85°C

Which type of microorganism grows in the absence of oxygen?

• Obligate aerobe

• Microaerophile

• Aerobe

• Anaerobe

What is the function of superoxide dismutase in aerobes?

• To inhibit microbial growth

• To protect against reactive oxygen species

• To produce oxygen

• To regulate temperature