From flower bud to flowering, after pollination (self-pollination and cross-pollination) and fertilization (when the pistil is mature, the stigma will secrete mucus, and the pollen falling on the stigma will germinate to form a pollen tube, which will grow indoors through the style until it reaches the ovule and form sperm in the growing pollen tube. After the pollen tube reaches the ovule, the top of the pollen tube breaks, and the sperm moves outward, and does not combine with the egg cells in the ovule to form a zygote, that is, a fertilized egg, which completes the whole sexual reproduction process and eventually develops into a seed.
Essential differences between sexual reproduction and asexual reproduction in plants
Asexual reproduction does not require pairing of germ cells, while sexual reproduction is based on meiosis. Generally, bisexual germ cells are combined through fertilization to maintain the stability of chromosome number. But whether it is combined with bisexual germ cells is not the essential difference between asexual reproduction and sexual reproduction. Take bees as an example: the egg cells formed by meiosis of queen bees can directly develop into drones, that is, they are produced by a queen bee. However, from the characteristics of drones, there are great differences between drones, drones and queen bees. Different from asexual reproduction, it belongs to parthenogenesis in sexual reproduction. Therefore, whether it undergoes meiosis or not is the essential difference between asexual reproduction and sexual reproduction.