Answer:

Anton van Leeuwenhoek made an important contribution to the development of the cell theory. in 1674 he algae and animalcules. Contributed to cell theory by believing that there were seeds or eggs too small to see by the eye being planted into food, and other things.

Answer:

Bluff po ang answer

Explanation:

It's existing

but the question said "pre-existing"

Hope my answer helps

and correct me if I'm wrong