Textbook Question
Which of the following items functions most like an autoclave?
a. Boiling pan
b. Incinerator
c. Microwave oven
d. Pressure cooker
612
views
11. Controlling Microbial Growth
Physical Methods to Control Microbial Growth
1:27 minutesProblem 6
Textbook Question
Describe five physical methods of microbial control.
Verified step by step guidance1
Identify that physical methods of microbial control involve techniques that use physical agents to reduce or eliminate microorganisms without the use of chemicals.
Describe Heat as a physical method, which includes moist heat (like autoclaving and boiling) and dry heat (such as incineration and hot air ovens) to denature proteins and destroy microbes.
Explain Filtration, where fluids or air are passed through filters with pores small enough to remove microorganisms, useful for heat-sensitive liquids and air sterilization.
Discuss Radiation, including ionizing radiation (like gamma rays and X-rays) that damages DNA, and non-ionizing radiation (such as UV light) that causes thymine dimers in DNA, inhibiting replication.
Mention other physical methods such as Desiccation (drying to inhibit microbial growth) and Osmotic Pressure (using high salt or sugar concentrations to create a hypertonic environment that dehydrates microbes).
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
1mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Physical Methods of Microbial Control
Physical methods use physical agents like heat, radiation, or filtration to reduce or eliminate microbial populations. These methods do not involve chemicals and are often used to sterilize or disinfect surfaces, liquids, and equipment.
Recommended video:
Guided course
01:46
Physical Methods to Control Microbial Growth
Heat-Based Methods
Heat is a common physical method that kills microbes by denaturing proteins and disrupting cell membranes. Examples include moist heat (autoclaving, boiling) and dry heat (incineration, hot air ovens), each effective against different types of microorganisms.
Recommended video:
Guided course
02:54Bases
Radiation and Filtration
Radiation methods like UV and ionizing radiation damage microbial DNA, preventing replication. Filtration physically removes microbes from liquids or air using membranes with pores small enough to trap microorganisms without killing them.
Recommended video:
Guided course
02:29Measuring Growth by Membrane Filtration
1:46mWatch next
Master Physical Methods to Control Microbial Growth with a bite sized video explanation from Jason
Start learningRelated Videos
Related Practice