Answer Key for Lesson 7 How Bacteria Are Killed

Start by focusing on the primary mechanisms that eliminate microorganisms, such as the use of heat, chemicals, and antibiotics. These methods disrupt the cellular structures or processes that are vital for the survival of the microorganisms.

Heat treatments, such as boiling or autoclaving, are commonly used to destroy harmful organisms by denaturing their proteins. These high temperatures break down the structure of enzymes and other cellular components, rendering the organisms inactive.

Chemicals like disinfectants work by damaging the cell walls or membranes of microorganisms. This prevents them from maintaining their integrity, ultimately leading to their destruction. Be sure to apply the appropriate concentration and contact time for effective disinfection.

Finally, antibiotics target specific functions within cells, such as protein synthesis or cell wall formation. By blocking these processes, antibiotics prevent the microorganism from multiplying and surviving in the host environment.