OBJECTIVE LIFE SCIENCE
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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in order to survive exposure to penicillin, bacteria developed a resistance to the drug
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a few bacteria became resistant to penicillin, and through sexual reproduction, most bacteria acquired the resistance
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penicillin never really successfully wiped out populations of bacteria, scientist did not use proper controls in their studies
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some bacteria were resistant to penicillin and their population spread rapidly, without competition from bacteria that were killed by penicillin
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Detailed explanation-1: -No sooner had the miraculous effects of penicillin become apparent to the general public, then the antibiotic started to be overused. This triggered selective pressure for the emergence of penicillin-resistant strains, which over a few years spread across different countries.
Detailed explanation-2: -When exposed to antibiotics, susceptible bacteria are killed; while excessive antibiotic use or their use for the wrong reasons can cause bacteria to become resistant and continue to grow and multiply. These resistant bacteria may spread and cause infections in other people.
Detailed explanation-3: -The main cause of antibiotic resistance is antibiotic use. When we use antibiotics, some bacteria die but resistant bacteria can survive and even multiply. The overuse of antibiotics makes resistant bacteria more common. The more we use antibiotics, the more chances bacteria have to become resistant to them.
Detailed explanation-4: -Penicillin resistance results either from the acquisition of plasmids that encode -lactamase or from chromosomal mutations. Quinolone-containing regimens are no longer recommended, because resistance to these drugs has been well documented.