Antibiotic resistance in bacteria is an example of which of the following?

• A. Stabilizing selection
• B. Disruptive selection
• C. Hardy-Weinberg equilibrium
• D. Macroevolution
• E. Directional selection

Answer: (E)

Verified step by step guidance

1. Understand the concept of antibiotic resistance: Antibiotic resistance occurs when bacteria evolve mechanisms to survive exposure to antibiotics that would normally kill them or inhibit their growth.
2. Review the types of natural selection: Natural selection can be categorized into stabilizing, disruptive, and directional selection, each affecting the distribution of traits in a population differently.
3. Define directional selection: Directional selection occurs when one extreme phenotype is favored over others, leading to a shift in the population's trait distribution towards that extreme.
4. Apply the concept to antibiotic resistance: In the case of antibiotic resistance, bacteria with resistance traits are favored and survive, while those without resistance are eliminated, causing a shift in the population towards resistant phenotypes.
5. Conclude that antibiotic resistance is an example of directional selection: The population of bacteria shifts towards increased resistance, demonstrating directional selection as the resistant bacteria are selected for survival.