EVOLUTION
HARDY WEINBERG EQUILIBRIUM
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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: -The most important mechanism of resistance to the penicillins and cephalosporins is antibiotic hydrolysis mediated by the bacterial enzyme beta-lactamase.
Detailed explanation-2: -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.
Detailed explanation-3: -Antimicrobial resistance is accelerated when the presence of antibiotics and antifungals pressure bacteria and fungi to adapt. Antibiotics and antifungals kill some germs that cause infections, but they also kill helpful germs that protect our body from infection. The antimicrobial-resistant germs survive and multiply.
Detailed explanation-4: -The spread of antibiotic resistance in pathogenic bacteria is a simple and elegant example of evolutionary adaptation by natural selection. Bacteria can become resistant to antibiotics through mutations that alter the cellular targets of antibiotics or by acquiring dedicated resistance genes from other bacteria.