Skip to main content
뒤로

Microbial Growth Conditions: Temperature, pH, and Salt Adaptations

컨트롤 버튼이 '내비게이션' 모드로 변경되었습니다.
1/16

이 집합의 용어 (16)

  • What are psychrophiles and their temperature range?

    Psychrophiles are microbes that thrive at very low temperatures, typically between -20°C and 10°C. They are adapted to cold environments like polar regions.

  • What are psychrotrophs and their temperature range?

    Psychrotrophs grow well at low temperatures but have a broader range, typically 0°C to 30°C. They can spoil refrigerated foods.

  • Define mesophiles and their temperature range.

    Mesophiles grow best at moderate temperatures, usually between 20°C and 45°C. Most human pathogens are mesophiles.

  • What are thermophiles and their temperature range?

    Thermophiles thrive at high temperatures, typically 45°C to 80°C, found in hot springs and compost heaps.

  • Describe extreme thermophiles and their temperature range.

    Extreme thermophiles grow optimally above 80°C, often in environments like hydrothermal vents.

  • What happens to microbes at low temperatures?

    Low temperatures slow enzyme activity and membrane fluidity, reducing microbial growth and metabolism.

  • What occurs to microbes at high temperatures?

    High temperatures can denature proteins and disrupt membranes, leading to cell death if beyond tolerance.

  • What determines a microbe's minimum, maximum, and optimal temperature?

    Enzyme stability, membrane composition, and protein structure determine the temperature range a microbe can survive.

  • Define acidophiles and their pH range.

    Acidophiles grow best at acidic pH, usually below pH 5, such as Ferroplasma species.

  • What are alkaliphiles and their pH range?

    Alkaliphiles thrive in basic environments, typically pH 9 or above, like some Bacillus species.

  • Describe neutralophiles and their pH range.

    Neutralophiles prefer neutral pH around 6.5 to 7.5, including most human-associated microbes.

  • How do microbes survive in different pH environments?

    They use mechanisms like proton pumps, buffering compounds, and specialized enzymes to maintain internal pH.

  • What is a halophile?

    Halophiles are microbes that require high salt concentrations to grow, often found in salt lakes and saline soils.

  • How do halophiles combat osmotic stress?

    They accumulate compatible solutes or ions internally to balance osmotic pressure and prevent dehydration.

  • Difference between halophiles and facultative halophiles?

    Halophiles require high salt to grow, while facultative halophiles tolerate but do not require high salt.

  • Why can't most microbes survive in high salt environments?

    High salt causes osmotic stress, leading to water loss and cell plasmolysis, which most microbes cannot tolerate.