Exam 2 Prep Quiz

What is antibiotic resistance?

• The ability for microbes to resist biotic changes in their habitat.

• The ability for microbes like bacteria to resist drugs that usually kill them.

• The ability for microbes to benefit the health of their host by aiding in food digestion

How does antibiotic resistance occur?

• Evolution through natural selection as resistant microbes survive and reproduce more offspring than non-resistant microbes.
• Evolution through genetic drift as the microbe population is randomly and drastically reduced, and the founders of the new population pass down their genes.
• Evolution through gene flow between populations of similar bacteria that already have antibiotic resistance.
• Evolution through individuals that have a new need to be resistant to antibiotics, so their offspring then gain antibiotic resistance.

What is the source of new traits in populations of organisms?

• Genetic drift
• The need for new traits to match the changing environment
• Gene flow
• Random genetic mutation

Why don't individuals evolve?

• Natural selection happens too slowly for individuals to be impacted and evolve in response.
• Evolution is defined as the change in allele frequency within a population over time. An individual cannot change its genes over time.
• Individuals do evolve, but only in response to significant environmental change.

Define fitness in biology terms.

Which of these mechanisms of evolution are NON-adaptive?

• Natural selection
• Gene flow
• Disruptive selection
• Genetic drift

How do you define a species?

Which is a reproductive barrier?

• A physical barrier that keeps two organisms from mating with eachother.
• A genetic barrier that prevents the offspring of two organisms from surviving very long.
• A physical barrier that separates two organisms from being close enough to come into contact.
• All of the above
• None of the above

Name an example of a prezygotic barrier.

Name an example of a postzygotic barrier.