Alex Is a Student with Strep Throat (Caused by a Strain

question 10

Multiple Choice

Alex is a student with Strep throat (caused by a strain of bacterium) who is given a prescription for an antibiotic and is told to take the drug for two weeks.After a week,he feels better and stops taking the drug.Two months later,Alex again shows symptoms of Strep throat and decides to finish the leftover antibiotic rather than going to the doctor again.Two months after that,he develops Strep throat for a third time and returns to the doctor.This time,the antibiotic does not work.The doctor runs a test and discovers that the bacterial strain Alex is carrying is antibiotic resistant.What most likely happened?

• A) Because the use of antibiotics lowers the effectiveness of the immune system, the student continually reinfected himself with the bacteria. The third time, the student happened to be reinfected with a resistant strain.
• B) When the student stopped taking the drug, a small number of bacteria-those that were more drug resistant-still survived in his body. Those bacteria repopulated his throat and, over time, drug-resistant alleles became more common.
• C) The student must have eaten produce that had been genetically engineered with antibiotic-resistant genes. When he consumed them, the bacteria in the student's throat picked up these genes through horizontal gene transfer.
• D) The antibiotic caused mutations in the bacterium. The more exposure to the antibiotic, the more mutations.

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Definitions:

Mental Age

A measure of an individual's cognitive ability compared to the average cognitive ability of a person of the same chronological age, often used in intellectual assessment.

Intelligence Quotient

A measure of an individual's cognitive abilities in comparison to the population, usually determined by an IQ test.

Chronological Age

The actual age of an individual measured in years from their date of birth to the current date.

Flynn Effect

The rise in average IQ scores that has occurred over the decades in many nations.