I believe that the areas are tropical and polar zones.
They have a coarse-grained texture.
Answer: natural selection
Matter can be broken down into two categories: pure substances<span> and </span>mixtures.Pure substances<span> are further broken down into elements and compounds. ... A chemical </span>substance<span> is composed of one type of atom or molecule. A </span>mixture<span> is composed of different types of atoms or molecules that are not chemically bonded</span>
Answer:
The answer is 3. Double Helix.