Skip to main content
Pearson+ LogoPearson+ Logo
Ch. 20 - Population Genetics and Evolution at the Population, Species, and Molecular Levels
Sanders - Genetic Analysis: An Integrated Approach 3rd Edition
Sanders3rd EditionGenetic Analysis: An Integrated ApproachISBN: 9780135564172Not the one you use?Change textbook
All textbooksSanders 3rd EditionCh. 20 - Population Genetics and Evolution at the Population, Species, and Molecular LevelsProblem 12
Chapter 20, Problem 12

Biologists have proposed that the use of antibiotics to treat human infectious disease has played a role in the evolution of widespread antibiotic resistance in several bacterial species, including Staphylococcus aureus and the bacteria causing gonorrhea, tuberculosis, and other infectious diseases. Explain how the evolutionary mechanisms mutation and natural selection may have contributed to the development of antibiotic resistance.

Verified step by step guidance
1
Understand that mutation is a random change in the DNA sequence of an organism, which can lead to new traits, such as antibiotic resistance.
Recognize that when bacteria are exposed to antibiotics, those with mutations that confer resistance have a survival advantage.
Realize that natural selection occurs as these resistant bacteria survive and reproduce more successfully than non-resistant ones.
Acknowledge that over time, the frequency of resistant bacteria increases in the population, leading to widespread antibiotic resistance.
Consider that the misuse or overuse of antibiotics can accelerate this process by creating more selective pressure for resistant strains.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
2m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Mutation

Mutation refers to changes in the DNA sequence of an organism's genome. These alterations can occur spontaneously or be induced by environmental factors, such as exposure to antibiotics. In bacteria, mutations can lead to traits that confer resistance to antibiotics, allowing those bacteria to survive and reproduce in the presence of these drugs.
Recommended video:
Guided course
10:48
Mutations and Phenotypes

Natural Selection

Natural selection is the process by which organisms better adapted to their environment tend to survive and produce more offspring. In the context of antibiotic resistance, when antibiotics are used, susceptible bacteria are killed, while those with mutations that confer resistance survive. Over time, these resistant bacteria become more prevalent in the population, leading to a higher overall level of resistance.
Recommended video:
Guided course
05:54
Natural Selection

Antibiotic Resistance

Antibiotic resistance occurs when bacteria evolve mechanisms to withstand the effects of drugs that once killed them or inhibited their growth. This phenomenon is a significant public health concern, as it can lead to treatment failures and the spread of resistant infections. Understanding the roles of mutation and natural selection is crucial for addressing and mitigating the impact of antibiotic resistance.
Recommended video:
Guided course
02:19
R Plasmid
Related Practice
Textbook Question

The ability to taste the bitter compound phenylthiocarbamide (PTC) is an autosomal dominant trait. The inability to taste PTC is a recessive condition. In a sample of 500 people, 360 have the ability to taste PTC and 140 do not. Calculate the frequency of the dominant allele.

462
views
Textbook Question

The ability to taste the bitter compound phenylthiocarbamide (PTC) is an autosomal dominant trait. The inability to taste PTC is a recessive condition. In a sample of 500 people, 360 have the ability to taste PTC and 140 do not. Calculate the frequency of each genotype.

1235
views
Textbook Question

The figure illustrates the effect of an ethanol-rich and an ethanol-free environment on the frequency of the Drosophila AdhF allele in four populations in a 50-generation laboratory experiment. Population 1 and population 2 were reared for 50 generations in a high-ethanol environment, while control 1 and control 2 populations were reared for 50 generations in a zero-ethanol environment. Describe the effect of each environment on the populations, and state any conclusions you can reach about the role of any of the evolutionary processes in producing these effects.

498
views
Textbook Question

Two populations of deer, one of them large and living in a mainland forest and the other small and inhabiting a forest on an island, regularly exchange members that migrate across a land bridge that connects the island to the mainland. If you compared the allele frequencies in the two populations, what would you expect to find?

422
views
Textbook Question

Two populations of deer, one of them large and living in a mainland forest and the other small and inhabiting a forest on an island, regularly exchange members that migrate across a land bridge that connects the island to the mainland. An earthquake destroys the bridge between the island and the mainland, making migration impossible for the deer. What do you expect will happen to allele frequencies in the two populations over the following 10 generations?

455
views
Textbook Question

Two populations of deer, one of them large and living in a mainland forest and the other small and inhabiting a forest on an island, regularly exchange members that migrate across a land bridge that connects the island to the mainland. In which population do you expect to see the greatest allele frequency change? Why?

447
views