Concept explainers
The alleles responsible for antibiotic resistance in bacteria
- a. arise in response to the presence of antibiotics.
- b. are identical to the alleles responsible for pesticide resistance in insects.
- c. are present in bacterial populations that have never been exposed to antibiotics.
- d. are formed by interactions between antibiotic molecules and bacterial DNA.
Introduction:
Antibiotic resistance is the property of the bacteria to defend themselves from the effect of antibiotics. Antibiotics are the chemical compounds that are synthesized by the microorganisms and can also be synthesized in the laboratory. The bacterium posses the ability to achieve resistance against a particular antibody as its genome has the ability to encode proteins that can neutralize the antibiotic.
Answer to Problem 1MC
Correct answer:
The alleles responsible for antibiotic resistance in bacteria are present in bacterial populations that have never been exposed to antibiotics. Therefore, option (c) is correct.
Option (c) is given as “are present in bacterial populations that have never been exposed to antibiotics”.
Explanation of Solution
Justify reason for the correct statement:
The bacterial population has the gene for the antibiotic resistance in them, even if they have never been exposed to antibiotics before. The resistance is attained after the gene is activated. The gene is activated when the organism comes in contact with the antibiotic.
Hence, option (c) is correct.
Justify reasons for the incorrect statements:
Option (a) is given as “arise in response to the presence of antibiotics.”
Antibiotic resistance gene is present inside the bacteria even before it comes in contact with the antibody. Hence, it is a wrong answer.
Option (b) is given as “are identical to the alleles responsible for pesticide resistance in insects.”
The allele for pesticide resistance in insects is not identical to the antibiotic resistance in bacteria. Hence, it is a wrong answer.
Option (d) is given as “are formed by interactions between antibiotic molecules and bacterial DNA.”
The antibiotic molecules need not interact with the bacteria for the bacteria to possess the antibiotic resistance gene. Hence, it is a wrong answer.
Hence, options (a), (b), and (d) are incorrect.
The gene for the antibiotic resistance is present in the bacterial population that has not yet come in contact with the antibiotic.
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Chapter 16 Solutions
Biology
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