DENDROLOGY

Detailed explanation-1: -Haploid cells undergo mitosis to produce a gametophyte. The gametophyte produces haploid gametes which fuse to form a diploid zygotic sporophyte . Alternation of generations is a reproductive cycle of certain vascular plants, fungi, and protists.

Detailed explanation-2: -The haploid gametophyte produces the gametes, or sperm and egg, by mitosis. Remember, gametes are haploid, having one set of chromosomes. Then, the sperm fertilizes the egg, producing a diploid zygote that develops into the sporophyte, which of course, is diploid.

Detailed explanation-3: -Alternation of generations means that plants alternate between two different life stages, or generations, in their life cycle; a haploid stage called gametophyte and a diploid stage called sporophyte. The terms haploid and diploid refer to the number of chromosomes contained in the cells.