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1204 OoBM - vo 6.1 Introd SCI-201 -P 6.3 Respire Scl201. X @& Newtab | Chat Thread + 0 Cc 23 webtexts.com/courses/85310/traditional_book/chi 4% & (@) Mf contents OURLIVING WORLD HANDWASHING Alcohol-based hand sanitizers are reasonably effective at sterilizing skin, but did you know that ordinary soap is superior in removing pathogens? The Centers for Disease Control and Prevention urge us to wash our hands to stop diseases like the flu and COVID-19 from infecting us and spreading to others. More specifically, we should wash our hands with soap and water for at least 20 seconds before eating or touching our faces and after blowing our noses, coughing, or sneezing. But why is this basic practice so important to stop diseases from spreading? And how does it work to destroy the virus? Let's start with soap. Soap is an amphiphile, a complex molecule that has two ends. One end is attracted to and binds to water; the other end binds to fat. These two ends of the soap molecule are the key in its ability to destroy the COVID-19 virus. Many viruses are encased in an envelope made of proteins and fat. You've previously learned that fats do not dissolve in water, but the end of the soap molecule burrows into the fat of the virus envelope. It breaks apart the relatively weak bonds that hold the envelope together. Once the envelope is gone, all the parts of the virus quickly dissolve in the water and disappear down the drain. MULTIPLE-CHOICE QUESTION How does handwashing with soap and water work to prevent the spread of viruses? O Soap disrupts the virus's protective envelope so that it can dissolve in water. ) Viruses can survive for up to 20 seconds of soap exposure. () Soap destroys all micro-organisms