New forms of drug-resistant bacteria can evolve quickly because
a
when a drug kills most of the bacteria, the ones left to breed are those that have a natural resistance to the drug.

b
when scientists genetically engineer bacteria they use natural selection.

c
scientists use extinction to selectively breed bacteria.

d
a drug causes mutations in the bacteria, leaving only mutated bacteria left to breed.

Which osmotic and ionic strategies must marine teleost fishes employ?

If water were a non polar molecule, how would its properties be different ? a.) water would be a much lighter molecule b.) water would be able to climb up inside plants c.)water would not be able to form hydrogen bonds d.) water would stick together much more strongly

Astudent reads the following text in a science book: scientific evidence tells us that the cause of earths four seasons is the tilt of earth as it revolves around the sound the student is instructed to illustrate this information in a science book. how will the student illustrate winter in the northern hemisphere? a.earths northern hemisphere will tilt away from the sun. b. earths northern hemisphere will tilt toward the sun. c.earths orbit will be farther away than from the sun d. earths southern hemisphere will tilt away from the sun.