Does the amount of nutrition, scale with the size of the fruit?

Way back in 7th grade general science class (circa 1965) we learned about “alternation of generations” in which plants, most visibly in lower species like ferns and mosses, alternate between sporophyte and gametophyte generations. It was mentioned that this pattern continues to exist in all plant life, even the more highly evolved forms – it’s just that one one the generations has become by far the most dominant and visible, and the other has become reduced to the point of being nearly vestigial.

Is this all correct?

Depending on what is actually correct about this, it may feed into the question of whether adjacent apples share DNA with each other or their parent tree. Can someone clarify?