I believe this is true since mRNA is directly translated from DNA.
Answer:
Extra change in plant population would have deep strong roots with tall trunks
Cells specialize (have different functions/organelle counts, etc) when they selectively activate (turn on) certain genes in their copies of DNA in the cell nucleus.
I believe the answer is a. thick layer of blubber
Mammal is an warm-blooded animal that need to keep their body warm. Organ that could insulate the heat would be beneficial to keep the temperature, like layer of fat or thick fur. The example of marine mammals would be dolphin, whale, sea lion and polar bear. Thick fur will not give much benefit for mammals in water, so only polar bear have thick fur. But all of them has thick layer of blubber, so option A will be the most appropriate.
Measure their heart rate beforethe test