True-breeding flies with singed bristles (s) and normal wings (l) were crossed to true-breeding flies with normal bristles (s) and vestigial wings (l). all f1 offspring had normal wings and normal bristles. (note: assume that neither of these genes is x-linked.) the f1 offspring were then crossed to flies with singed bristles and vestigial wings. for the f2 offspring, what genotypes and phenotypes are possible? which f2 offspring are recombinant and which are nonrecombinant? what will be the ratios of the f2 offspring if independent assortment is taking place? how will the ratios be affected by linkage?

Why do mutations in genes affect traits? o a. genes determine what type of mutagens an organism has. o b. genes produce proteins that cause traits. o c. genes affect how many chromosomes an organism has o d. genes code for carbohydrates that influence traits.

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.

The energy required to vaporize a certain amount of a substance is greater than the amount of energy necessary to raise the temperature of the same amout of that substance by 1 degreee celcius