The reason both of these are valid scientific hypotheses is because A) scientists with different educational backgrounds may put forth different hypotheses to explain the same data.
This approach in science is vital in making progress and has helped to explain many phenomena in the past. When scientists explain data using different approaches, they come to a more comprehensive conclusion.
Lipids provide long term energy storage
One of the daughter cell would have an extra chromosome while the other would be short one. It's called nondisjunction
