RNA has great capability as a genetic molecule; it once had to carry on hereditary processes on its own. It now seems certain that RNA was the first molecule of heredity, so it evolved all the essential methods for storing and expressing genetic information before DNA came onto the scene.
Many scientists agree that the universe is about 13 billion years old.
<span>The lamp switch was a neutral stimulus that elicited a conditioned response after a period of time. This is a clear example of conditioned response.</span>
