Answer: alternative D.
Explanation: For the DNA to have the double strand structure, it is necessary to copy the sequence of the existing DNA strand in a complementary sequence of nucleotides, forming hydrogen bonds between them. The mRNA also uses this strategy when reading the DNA strand during the transcription, in order for the translation to begin.
Answer:
It is also one of the world's most important commercial waterways and one of North America's great migration routes for both birds and fishes. Native Americans lived along its banks and used the river for sustenance and transportation.
Explanation:
The new species come from old ancestors of the animals that were there, over time they slowly evolved, and they adapted to that new environment.
They are connected by tendons