Hypotheses must be provable. If scientists cannot prove a "hypothesis" right or wrong, they need to change it to a legitimate hypothesis - something you can prove.
If it is proven wrong, they can change certain aspects of it to make a more specific experiment.
Answer:
I the organelle goes to the second row on the left
Francis Crick discovered the DNA structure.
Answer:
A Y-chromosome
Explanation:
Males have one X and one Y chromosome