Their DNA has been altered, and they have grown a immunity against this weed killer, as their DNA quickly identifies the weed kill as toxic.
Water is not wet. Water only has the ability to get other things wet
They don't swell because of osmosis.
The fact of many different things or people being included in something; a range of different things or people
Diversity definition, the state or fact of being diverse; difference; unlikeness: diversity of opinion
The answer to the question presented above would be 'require frequent rainfall'. A plant native to the chaparral would be expected to require frequent rainfall. This is because it cannot survive in dry lands and without constant water.