The one that was so momentous about the "twofold" some portion of the twofold helix atom is it proposed how hereditary data could be replicated and acquired. Double helix is a long, straight atom made of littler units called nucleotides that shape a chain.
To answer your question: the nucleus has a membrane.
Answer is B. Heliotropism
<span>The sequence of three bases (triplet) in a transfer RNA molecule</span>
Desertification is the process where fertile land becomes a desert.
Well one way desertification could impact an environment could be by a problem called OVERGRAZING.
Overgrazing happens when goats and cattle are kept in the same area for too long which results in then eating all the vegetation. If all vegetation is eaten, it is unlikely for it to grown back. Changes in political boundaries and companies buying land means that farmers rely on the water and land around them. This means farmers don't regularly move to new fertile areas.