How does a plant’s sporophyte generation differ from its gametophyte generation?

In botany, plants undergo an alternation of generations between two distinct, multicellular phases: the sporophyte and the gametophyte. These generations differ primarily in their chromosomal makeup, reproductive function, and dominance within the life cycle.123

Key Differences

• Chromosomal Status: The sporophyte is diploid ($2n$), meaning it contains two sets of chromosomes. The gametophyte is haploid ($1n$), containing only one set.123
• Reproductive Function: The sporophyte produces spores through meiosis. These spores develop into gametophytes, which produce gametes (eggs and sperm) through mitosis. The fusion of gametes during fertilization creates a zygote, which grows into a new sporophyte.143
• Dominance: The relative importance of these phases has shifted over evolutionary time. In primitive bryophytes, the gametophyte is the dominant, independent, and long-lived phase, while the sporophyte is dependent on it. Conversely, in vascular plants, the sporophyte is the dominant, independent phase, and the gametophyte is significantly reduced.1453