6. Select the scenario in which a mutation may become fixed in a population.
A mutation causing light skin shows up in a population of people living near the equator in South America.
A mutation for a stubby tail occurs in a population of Eastern gray squirrels, which normally have long, bushy tails.
Several bacteria in a population resistant to the antibiotic erythromycin show susceptibility to erythromycin because of a recent mutation.
A mutation occurs in a population of brown toads, causing green stripes that allow for better camouflaging in its habitat.
In a population of people whose main food source is the milk of their livestock, a mutation for lactose intolerance appears.

In 1959, doctors began using the powerful antibiotic methicillin to treat infections of staphylococcus aureus, but within two years, methicillin-resistant strains of s. aureus (mrsa) appeared. how did the resistant strains of s. aureus emerge? in 1959, doctors began using the powerful antibiotic methicillin to treat infections of staphylococcus aureus, but within two years, methicillin-resistant strains of s. aureus (mrsa) appeared. how did the resistant strains of s. aureus emerge? staphylococcus aureus bacteria that were able to synthesize cell walls using a protein that was not affected by methicillin survived the methicillin treatments and reproduced at higher rates than did other individuals. over time, these resistant individuals became increasingly common. in response to treatment of staphylococcus aureus infections with methicillin, some bacteria began to synthesize cell walls using a protein that was not affected by methicillin. these bacteria survived the methicillin treatments and reproduced at higher rates than did other individuals. over time, these resistant individuals became increasingly common. in response to treatment of staphylococcus aureus infections with methicillin, bacterial populations gradually began to synthesize cell walls using a protein that was not affected by methicillin.

Describe the function of the endomembrane system? what organelles are involved?

9. the history of life on earth is recorded in