1Give a reason: variation alone is not the factor behind the origin of a new species.
2Distinguish between variation and mutation.
3Distinguish between Darwin's theory and De Vries's theory.
4State the features of mutation.
5How does mutation help evolution?
6Make it clear that mutation is not the main factor of evolution but one additional factor.
7Some people have 6 fingers on one hand. What kind of change is this, why does it appear, and how does it help evolution?
8What are a mutant and a mutagen?
9What is the difference between somatogenic variation and blastogenic variation? Write with examples.
10What is environmental variation? Give an example.
11What did Hugo De Vries find in his experiment, and what conclusion did he draw?